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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Simple NUMA memory policy for the Linux kernel.
3 *
4 * Copyright 2003,2004 Andi Kleen, SuSE Labs.
Christoph Lameter8bccd852005-10-29 18:16:59 -07005 * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc.
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 * Subject to the GNU Public License, version 2.
7 *
8 * NUMA policy allows the user to give hints in which node(s) memory should
9 * be allocated.
10 *
11 * Support four policies per VMA and per process:
12 *
13 * The VMA policy has priority over the process policy for a page fault.
14 *
15 * interleave Allocate memory interleaved over a set of nodes,
16 * with normal fallback if it fails.
17 * For VMA based allocations this interleaves based on the
18 * offset into the backing object or offset into the mapping
19 * for anonymous memory. For process policy an process counter
20 * is used.
Christoph Lameter8bccd852005-10-29 18:16:59 -070021 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070022 * bind Only allocate memory on a specific set of nodes,
23 * no fallback.
Christoph Lameter8bccd852005-10-29 18:16:59 -070024 * FIXME: memory is allocated starting with the first node
25 * to the last. It would be better if bind would truly restrict
26 * the allocation to memory nodes instead
27 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 * preferred Try a specific node first before normal fallback.
29 * As a special case node -1 here means do the allocation
30 * on the local CPU. This is normally identical to default,
31 * but useful to set in a VMA when you have a non default
32 * process policy.
Christoph Lameter8bccd852005-10-29 18:16:59 -070033 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 * default Allocate on the local node first, or when on a VMA
35 * use the process policy. This is what Linux always did
36 * in a NUMA aware kernel and still does by, ahem, default.
37 *
38 * The process policy is applied for most non interrupt memory allocations
39 * in that process' context. Interrupts ignore the policies and always
40 * try to allocate on the local CPU. The VMA policy is only applied for memory
41 * allocations for a VMA in the VM.
42 *
43 * Currently there are a few corner cases in swapping where the policy
44 * is not applied, but the majority should be handled. When process policy
45 * is used it is not remembered over swap outs/swap ins.
46 *
47 * Only the highest zone in the zone hierarchy gets policied. Allocations
48 * requesting a lower zone just use default policy. This implies that
49 * on systems with highmem kernel lowmem allocation don't get policied.
50 * Same with GFP_DMA allocations.
51 *
52 * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between
53 * all users and remembered even when nobody has memory mapped.
54 */
55
56/* Notebook:
57 fix mmap readahead to honour policy and enable policy for any page cache
58 object
59 statistics for bigpages
60 global policy for page cache? currently it uses process policy. Requires
61 first item above.
62 handle mremap for shared memory (currently ignored for the policy)
63 grows down?
64 make bind policy root only? It can trigger oom much faster and the
65 kernel is not always grateful with that.
Linus Torvalds1da177e2005-04-16 15:20:36 -070066*/
67
68#include <linux/mempolicy.h>
69#include <linux/mm.h>
70#include <linux/highmem.h>
71#include <linux/hugetlb.h>
72#include <linux/kernel.h>
73#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070074#include <linux/nodemask.h>
75#include <linux/cpuset.h>
76#include <linux/gfp.h>
77#include <linux/slab.h>
78#include <linux/string.h>
79#include <linux/module.h>
Pavel Emelyanovb4888932007-10-18 23:40:14 -070080#include <linux/nsproxy.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070081#include <linux/interrupt.h>
82#include <linux/init.h>
83#include <linux/compat.h>
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080084#include <linux/swap.h>
Christoph Lameter1a75a6c2006-01-08 01:01:02 -080085#include <linux/seq_file.h>
86#include <linux/proc_fs.h>
Christoph Lameterb20a3502006-03-22 00:09:12 -080087#include <linux/migrate.h>
Christoph Lameter95a402c2006-06-23 02:03:53 -070088#include <linux/rmap.h>
David Quigley86c3a762006-06-23 02:04:02 -070089#include <linux/security.h>
Adrian Bunkdbcb0f12007-10-16 01:26:26 -070090#include <linux/syscalls.h>
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -070091#include <linux/ctype.h>
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080092
Linus Torvalds1da177e2005-04-16 15:20:36 -070093#include <asm/tlbflush.h>
94#include <asm/uaccess.h>
95
Nick Piggin62695a82008-10-18 20:26:09 -070096#include "internal.h"
97
Christoph Lameter38e35862006-01-08 01:01:01 -080098/* Internal flags */
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -080099#define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */
Christoph Lameter38e35862006-01-08 01:01:01 -0800100#define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */
Christoph Lameter1a75a6c2006-01-08 01:01:02 -0800101#define MPOL_MF_STATS (MPOL_MF_INTERNAL << 2) /* Gather statistics */
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800102
Pekka Enbergfcc234f2006-03-22 00:08:13 -0800103static struct kmem_cache *policy_cache;
104static struct kmem_cache *sn_cache;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106/* Highest zone. An specific allocation for a zone below that is not
107 policied. */
Christoph Lameter62672762007-02-10 01:43:07 -0800108enum zone_type policy_zone = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700110/*
111 * run-time system-wide default policy => local allocation
112 */
Andi Kleend42c6992005-07-06 19:56:03 +0200113struct mempolicy default_policy = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 .refcnt = ATOMIC_INIT(1), /* never free it */
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700115 .mode = MPOL_PREFERRED,
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -0700116 .flags = MPOL_F_LOCAL,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117};
118
David Rientjes37012942008-04-28 02:12:33 -0700119static const struct mempolicy_operations {
120 int (*create)(struct mempolicy *pol, const nodemask_t *nodes);
121 void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes);
122} mpol_ops[MPOL_MAX];
123
Mel Gorman19770b32008-04-28 02:12:18 -0700124/* Check that the nodemask contains at least one populated zone */
David Rientjes37012942008-04-28 02:12:33 -0700125static int is_valid_nodemask(const nodemask_t *nodemask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126{
Mel Gorman19770b32008-04-28 02:12:18 -0700127 int nd, k;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
Mel Gorman19770b32008-04-28 02:12:18 -0700129 /* Check that there is something useful in this mask */
130 k = policy_zone;
131
132 for_each_node_mask(nd, *nodemask) {
133 struct zone *z;
134
135 for (k = 0; k <= policy_zone; k++) {
136 z = &NODE_DATA(nd)->node_zones[k];
137 if (z->present_pages > 0)
138 return 1;
Andi Kleendd942ae2006-02-17 01:39:16 +0100139 }
140 }
Mel Gorman19770b32008-04-28 02:12:18 -0700141
142 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143}
144
David Rientjesf5b087b2008-04-28 02:12:27 -0700145static inline int mpol_store_user_nodemask(const struct mempolicy *pol)
146{
David Rientjes4c50bc02008-04-28 02:12:30 -0700147 return pol->flags & (MPOL_F_STATIC_NODES | MPOL_F_RELATIVE_NODES);
148}
149
150static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig,
151 const nodemask_t *rel)
152{
153 nodemask_t tmp;
154 nodes_fold(tmp, *orig, nodes_weight(*rel));
155 nodes_onto(*ret, tmp, *rel);
David Rientjesf5b087b2008-04-28 02:12:27 -0700156}
157
David Rientjes37012942008-04-28 02:12:33 -0700158static int mpol_new_interleave(struct mempolicy *pol, const nodemask_t *nodes)
159{
160 if (nodes_empty(*nodes))
161 return -EINVAL;
162 pol->v.nodes = *nodes;
163 return 0;
164}
165
166static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes)
167{
168 if (!nodes)
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -0700169 pol->flags |= MPOL_F_LOCAL; /* local allocation */
David Rientjes37012942008-04-28 02:12:33 -0700170 else if (nodes_empty(*nodes))
171 return -EINVAL; /* no allowed nodes */
172 else
173 pol->v.preferred_node = first_node(*nodes);
174 return 0;
175}
176
177static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes)
178{
179 if (!is_valid_nodemask(nodes))
180 return -EINVAL;
181 pol->v.nodes = *nodes;
182 return 0;
183}
184
Miao Xie58568d22009-06-16 15:31:49 -0700185/*
186 * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if
187 * any, for the new policy. mpol_new() has already validated the nodes
188 * parameter with respect to the policy mode and flags. But, we need to
189 * handle an empty nodemask with MPOL_PREFERRED here.
190 *
191 * Must be called holding task's alloc_lock to protect task's mems_allowed
192 * and mempolicy. May also be called holding the mmap_semaphore for write.
193 */
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700194static int mpol_set_nodemask(struct mempolicy *pol,
195 const nodemask_t *nodes, struct nodemask_scratch *nsc)
Miao Xie58568d22009-06-16 15:31:49 -0700196{
Miao Xie58568d22009-06-16 15:31:49 -0700197 int ret;
198
199 /* if mode is MPOL_DEFAULT, pol is NULL. This is right. */
200 if (pol == NULL)
201 return 0;
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700202 /* Check N_HIGH_MEMORY */
203 nodes_and(nsc->mask1,
204 cpuset_current_mems_allowed, node_states[N_HIGH_MEMORY]);
Miao Xie58568d22009-06-16 15:31:49 -0700205
206 VM_BUG_ON(!nodes);
207 if (pol->mode == MPOL_PREFERRED && nodes_empty(*nodes))
208 nodes = NULL; /* explicit local allocation */
209 else {
210 if (pol->flags & MPOL_F_RELATIVE_NODES)
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700211 mpol_relative_nodemask(&nsc->mask2, nodes,&nsc->mask1);
Miao Xie58568d22009-06-16 15:31:49 -0700212 else
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700213 nodes_and(nsc->mask2, *nodes, nsc->mask1);
214
Miao Xie58568d22009-06-16 15:31:49 -0700215 if (mpol_store_user_nodemask(pol))
216 pol->w.user_nodemask = *nodes;
217 else
218 pol->w.cpuset_mems_allowed =
219 cpuset_current_mems_allowed;
220 }
221
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700222 if (nodes)
223 ret = mpol_ops[pol->mode].create(pol, &nsc->mask2);
224 else
225 ret = mpol_ops[pol->mode].create(pol, NULL);
Miao Xie58568d22009-06-16 15:31:49 -0700226 return ret;
227}
228
229/*
230 * This function just creates a new policy, does some check and simple
231 * initialization. You must invoke mpol_set_nodemask() to set nodes.
232 */
David Rientjes028fec42008-04-28 02:12:25 -0700233static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags,
234 nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235{
236 struct mempolicy *policy;
237
David Rientjes028fec42008-04-28 02:12:25 -0700238 pr_debug("setting mode %d flags %d nodes[0] %lx\n",
239 mode, flags, nodes ? nodes_addr(*nodes)[0] : -1);
Paul Mundt140d5a42007-07-15 23:38:16 -0700240
David Rientjes3e1f0642008-04-28 02:12:34 -0700241 if (mode == MPOL_DEFAULT) {
242 if (nodes && !nodes_empty(*nodes))
David Rientjes37012942008-04-28 02:12:33 -0700243 return ERR_PTR(-EINVAL);
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700244 return NULL; /* simply delete any existing policy */
David Rientjes37012942008-04-28 02:12:33 -0700245 }
David Rientjes3e1f0642008-04-28 02:12:34 -0700246 VM_BUG_ON(!nodes);
247
248 /*
249 * MPOL_PREFERRED cannot be used with MPOL_F_STATIC_NODES or
250 * MPOL_F_RELATIVE_NODES if the nodemask is empty (local allocation).
251 * All other modes require a valid pointer to a non-empty nodemask.
252 */
253 if (mode == MPOL_PREFERRED) {
254 if (nodes_empty(*nodes)) {
255 if (((flags & MPOL_F_STATIC_NODES) ||
256 (flags & MPOL_F_RELATIVE_NODES)))
257 return ERR_PTR(-EINVAL);
David Rientjes3e1f0642008-04-28 02:12:34 -0700258 }
259 } else if (nodes_empty(*nodes))
260 return ERR_PTR(-EINVAL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261 policy = kmem_cache_alloc(policy_cache, GFP_KERNEL);
262 if (!policy)
263 return ERR_PTR(-ENOMEM);
264 atomic_set(&policy->refcnt, 1);
Lee Schermerhorn45c47452008-04-28 02:13:12 -0700265 policy->mode = mode;
David Rientjes3e1f0642008-04-28 02:12:34 -0700266 policy->flags = flags;
David Rientjesf5b087b2008-04-28 02:12:27 -0700267
David Rientjes37012942008-04-28 02:12:33 -0700268 return policy;
269}
270
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -0700271/* Slow path of a mpol destructor. */
272void __mpol_put(struct mempolicy *p)
273{
274 if (!atomic_dec_and_test(&p->refcnt))
275 return;
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -0700276 kmem_cache_free(policy_cache, p);
277}
278
David Rientjes37012942008-04-28 02:12:33 -0700279static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes)
280{
281}
282
283static void mpol_rebind_nodemask(struct mempolicy *pol,
284 const nodemask_t *nodes)
285{
286 nodemask_t tmp;
287
288 if (pol->flags & MPOL_F_STATIC_NODES)
289 nodes_and(tmp, pol->w.user_nodemask, *nodes);
290 else if (pol->flags & MPOL_F_RELATIVE_NODES)
291 mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
292 else {
293 nodes_remap(tmp, pol->v.nodes, pol->w.cpuset_mems_allowed,
294 *nodes);
295 pol->w.cpuset_mems_allowed = *nodes;
296 }
297
298 pol->v.nodes = tmp;
299 if (!node_isset(current->il_next, tmp)) {
300 current->il_next = next_node(current->il_next, tmp);
301 if (current->il_next >= MAX_NUMNODES)
302 current->il_next = first_node(tmp);
303 if (current->il_next >= MAX_NUMNODES)
304 current->il_next = numa_node_id();
305 }
306}
307
308static void mpol_rebind_preferred(struct mempolicy *pol,
309 const nodemask_t *nodes)
310{
311 nodemask_t tmp;
312
David Rientjes37012942008-04-28 02:12:33 -0700313 if (pol->flags & MPOL_F_STATIC_NODES) {
314 int node = first_node(pol->w.user_nodemask);
315
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -0700316 if (node_isset(node, *nodes)) {
David Rientjes37012942008-04-28 02:12:33 -0700317 pol->v.preferred_node = node;
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -0700318 pol->flags &= ~MPOL_F_LOCAL;
319 } else
320 pol->flags |= MPOL_F_LOCAL;
David Rientjes37012942008-04-28 02:12:33 -0700321 } else if (pol->flags & MPOL_F_RELATIVE_NODES) {
322 mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
323 pol->v.preferred_node = first_node(tmp);
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -0700324 } else if (!(pol->flags & MPOL_F_LOCAL)) {
David Rientjes37012942008-04-28 02:12:33 -0700325 pol->v.preferred_node = node_remap(pol->v.preferred_node,
326 pol->w.cpuset_mems_allowed,
327 *nodes);
328 pol->w.cpuset_mems_allowed = *nodes;
329 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330}
331
David Rientjes1d0d2682008-04-28 02:12:32 -0700332/* Migrate a policy to a different set of nodes */
333static void mpol_rebind_policy(struct mempolicy *pol,
334 const nodemask_t *newmask)
335{
David Rientjes1d0d2682008-04-28 02:12:32 -0700336 if (!pol)
337 return;
David Rientjes1d0d2682008-04-28 02:12:32 -0700338 if (!mpol_store_user_nodemask(pol) &&
339 nodes_equal(pol->w.cpuset_mems_allowed, *newmask))
340 return;
Lee Schermerhorn45c47452008-04-28 02:13:12 -0700341 mpol_ops[pol->mode].rebind(pol, newmask);
David Rientjes1d0d2682008-04-28 02:12:32 -0700342}
343
344/*
345 * Wrapper for mpol_rebind_policy() that just requires task
346 * pointer, and updates task mempolicy.
Miao Xie58568d22009-06-16 15:31:49 -0700347 *
348 * Called with task's alloc_lock held.
David Rientjes1d0d2682008-04-28 02:12:32 -0700349 */
350
351void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
352{
353 mpol_rebind_policy(tsk->mempolicy, new);
354}
355
356/*
357 * Rebind each vma in mm to new nodemask.
358 *
359 * Call holding a reference to mm. Takes mm->mmap_sem during call.
360 */
361
362void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
363{
364 struct vm_area_struct *vma;
365
366 down_write(&mm->mmap_sem);
367 for (vma = mm->mmap; vma; vma = vma->vm_next)
368 mpol_rebind_policy(vma->vm_policy, new);
369 up_write(&mm->mmap_sem);
370}
371
David Rientjes37012942008-04-28 02:12:33 -0700372static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
373 [MPOL_DEFAULT] = {
374 .rebind = mpol_rebind_default,
375 },
376 [MPOL_INTERLEAVE] = {
377 .create = mpol_new_interleave,
378 .rebind = mpol_rebind_nodemask,
379 },
380 [MPOL_PREFERRED] = {
381 .create = mpol_new_preferred,
382 .rebind = mpol_rebind_preferred,
383 },
384 [MPOL_BIND] = {
385 .create = mpol_new_bind,
386 .rebind = mpol_rebind_nodemask,
387 },
388};
389
Christoph Lameter397874d2006-03-06 15:42:53 -0800390static void gather_stats(struct page *, void *, int pte_dirty);
Christoph Lameterfc301282006-01-18 17:42:29 -0800391static void migrate_page_add(struct page *page, struct list_head *pagelist,
392 unsigned long flags);
Christoph Lameter1a75a6c2006-01-08 01:01:02 -0800393
Christoph Lameter38e35862006-01-08 01:01:01 -0800394/* Scan through pages checking if pages follow certain conditions. */
Nick Pigginb5810032005-10-29 18:16:12 -0700395static int check_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800396 unsigned long addr, unsigned long end,
397 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800398 void *private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399{
Hugh Dickins91612e02005-06-21 17:15:07 -0700400 pte_t *orig_pte;
401 pte_t *pte;
Hugh Dickins705e87c2005-10-29 18:16:27 -0700402 spinlock_t *ptl;
Hugh Dickins941150a2005-06-21 17:15:06 -0700403
Hugh Dickins705e87c2005-10-29 18:16:27 -0700404 orig_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
Hugh Dickins91612e02005-06-21 17:15:07 -0700405 do {
Linus Torvalds6aab3412005-11-28 14:34:23 -0800406 struct page *page;
Andy Whitcroft25ba77c2006-12-06 20:33:03 -0800407 int nid;
Hugh Dickins91612e02005-06-21 17:15:07 -0700408
409 if (!pte_present(*pte))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 continue;
Linus Torvalds6aab3412005-11-28 14:34:23 -0800411 page = vm_normal_page(vma, addr, *pte);
412 if (!page)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700413 continue;
Nick Piggin053837f2006-01-18 17:42:27 -0800414 /*
415 * The check for PageReserved here is important to avoid
416 * handling zero pages and other pages that may have been
417 * marked special by the system.
418 *
419 * If the PageReserved would not be checked here then f.e.
420 * the location of the zero page could have an influence
421 * on MPOL_MF_STRICT, zero pages would be counted for
422 * the per node stats, and there would be useless attempts
423 * to put zero pages on the migration list.
424 */
Christoph Lameterf4598c82006-01-12 01:05:20 -0800425 if (PageReserved(page))
426 continue;
Linus Torvalds6aab3412005-11-28 14:34:23 -0800427 nid = page_to_nid(page);
Christoph Lameter38e35862006-01-08 01:01:01 -0800428 if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
429 continue;
430
Christoph Lameter1a75a6c2006-01-08 01:01:02 -0800431 if (flags & MPOL_MF_STATS)
Christoph Lameter397874d2006-03-06 15:42:53 -0800432 gather_stats(page, private, pte_dirty(*pte));
Nick Piggin053837f2006-01-18 17:42:27 -0800433 else if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
Christoph Lameterfc301282006-01-18 17:42:29 -0800434 migrate_page_add(page, private, flags);
Christoph Lameter38e35862006-01-08 01:01:01 -0800435 else
436 break;
Hugh Dickins91612e02005-06-21 17:15:07 -0700437 } while (pte++, addr += PAGE_SIZE, addr != end);
Hugh Dickins705e87c2005-10-29 18:16:27 -0700438 pte_unmap_unlock(orig_pte, ptl);
Hugh Dickins91612e02005-06-21 17:15:07 -0700439 return addr != end;
440}
441
Nick Pigginb5810032005-10-29 18:16:12 -0700442static inline int check_pmd_range(struct vm_area_struct *vma, pud_t *pud,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800443 unsigned long addr, unsigned long end,
444 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800445 void *private)
Hugh Dickins91612e02005-06-21 17:15:07 -0700446{
447 pmd_t *pmd;
448 unsigned long next;
449
450 pmd = pmd_offset(pud, addr);
451 do {
452 next = pmd_addr_end(addr, end);
453 if (pmd_none_or_clear_bad(pmd))
454 continue;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800455 if (check_pte_range(vma, pmd, addr, next, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800456 flags, private))
Hugh Dickins91612e02005-06-21 17:15:07 -0700457 return -EIO;
458 } while (pmd++, addr = next, addr != end);
459 return 0;
460}
461
Nick Pigginb5810032005-10-29 18:16:12 -0700462static inline int check_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800463 unsigned long addr, unsigned long end,
464 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800465 void *private)
Hugh Dickins91612e02005-06-21 17:15:07 -0700466{
467 pud_t *pud;
468 unsigned long next;
469
470 pud = pud_offset(pgd, addr);
471 do {
472 next = pud_addr_end(addr, end);
473 if (pud_none_or_clear_bad(pud))
474 continue;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800475 if (check_pmd_range(vma, pud, addr, next, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800476 flags, private))
Hugh Dickins91612e02005-06-21 17:15:07 -0700477 return -EIO;
478 } while (pud++, addr = next, addr != end);
479 return 0;
480}
481
Nick Pigginb5810032005-10-29 18:16:12 -0700482static inline int check_pgd_range(struct vm_area_struct *vma,
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800483 unsigned long addr, unsigned long end,
484 const nodemask_t *nodes, unsigned long flags,
Christoph Lameter38e35862006-01-08 01:01:01 -0800485 void *private)
Hugh Dickins91612e02005-06-21 17:15:07 -0700486{
487 pgd_t *pgd;
488 unsigned long next;
489
Nick Pigginb5810032005-10-29 18:16:12 -0700490 pgd = pgd_offset(vma->vm_mm, addr);
Hugh Dickins91612e02005-06-21 17:15:07 -0700491 do {
492 next = pgd_addr_end(addr, end);
493 if (pgd_none_or_clear_bad(pgd))
494 continue;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800495 if (check_pud_range(vma, pgd, addr, next, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800496 flags, private))
Hugh Dickins91612e02005-06-21 17:15:07 -0700497 return -EIO;
498 } while (pgd++, addr = next, addr != end);
499 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500}
501
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800502/*
503 * Check if all pages in a range are on a set of nodes.
504 * If pagelist != NULL then isolate pages from the LRU and
505 * put them on the pagelist.
506 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507static struct vm_area_struct *
508check_range(struct mm_struct *mm, unsigned long start, unsigned long end,
Christoph Lameter38e35862006-01-08 01:01:01 -0800509 const nodemask_t *nodes, unsigned long flags, void *private)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510{
511 int err;
512 struct vm_area_struct *first, *vma, *prev;
513
Nick Piggin053837f2006-01-18 17:42:27 -0800514
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 first = find_vma(mm, start);
516 if (!first)
517 return ERR_PTR(-EFAULT);
518 prev = NULL;
519 for (vma = first; vma && vma->vm_start < end; vma = vma->vm_next) {
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800520 if (!(flags & MPOL_MF_DISCONTIG_OK)) {
521 if (!vma->vm_next && vma->vm_end < end)
522 return ERR_PTR(-EFAULT);
523 if (prev && prev->vm_end < vma->vm_start)
524 return ERR_PTR(-EFAULT);
525 }
526 if (!is_vm_hugetlb_page(vma) &&
527 ((flags & MPOL_MF_STRICT) ||
528 ((flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) &&
529 vma_migratable(vma)))) {
Andi Kleen5b952b32005-09-13 01:25:08 -0700530 unsigned long endvma = vma->vm_end;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800531
Andi Kleen5b952b32005-09-13 01:25:08 -0700532 if (endvma > end)
533 endvma = end;
534 if (vma->vm_start > start)
535 start = vma->vm_start;
Christoph Lameterdc9aa5b2006-01-08 01:00:50 -0800536 err = check_pgd_range(vma, start, endvma, nodes,
Christoph Lameter38e35862006-01-08 01:01:01 -0800537 flags, private);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700538 if (err) {
539 first = ERR_PTR(err);
540 break;
541 }
542 }
543 prev = vma;
544 }
545 return first;
546}
547
548/* Apply policy to a single VMA */
549static int policy_vma(struct vm_area_struct *vma, struct mempolicy *new)
550{
551 int err = 0;
552 struct mempolicy *old = vma->vm_policy;
553
Paul Mundt140d5a42007-07-15 23:38:16 -0700554 pr_debug("vma %lx-%lx/%lx vm_ops %p vm_file %p set_policy %p\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 vma->vm_start, vma->vm_end, vma->vm_pgoff,
556 vma->vm_ops, vma->vm_file,
557 vma->vm_ops ? vma->vm_ops->set_policy : NULL);
558
559 if (vma->vm_ops && vma->vm_ops->set_policy)
560 err = vma->vm_ops->set_policy(vma, new);
561 if (!err) {
562 mpol_get(new);
563 vma->vm_policy = new;
Lee Schermerhornf0be3d32008-04-28 02:13:08 -0700564 mpol_put(old);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565 }
566 return err;
567}
568
569/* Step 2: apply policy to a range and do splits. */
570static int mbind_range(struct vm_area_struct *vma, unsigned long start,
571 unsigned long end, struct mempolicy *new)
572{
573 struct vm_area_struct *next;
574 int err;
575
576 err = 0;
577 for (; vma && vma->vm_start < end; vma = next) {
578 next = vma->vm_next;
579 if (vma->vm_start < start)
580 err = split_vma(vma->vm_mm, vma, start, 1);
581 if (!err && vma->vm_end > end)
582 err = split_vma(vma->vm_mm, vma, end, 0);
583 if (!err)
584 err = policy_vma(vma, new);
585 if (err)
586 break;
587 }
588 return err;
589}
590
Paul Jacksonc61afb12006-03-24 03:16:08 -0800591/*
592 * Update task->flags PF_MEMPOLICY bit: set iff non-default
593 * mempolicy. Allows more rapid checking of this (combined perhaps
594 * with other PF_* flag bits) on memory allocation hot code paths.
595 *
596 * If called from outside this file, the task 'p' should -only- be
597 * a newly forked child not yet visible on the task list, because
598 * manipulating the task flags of a visible task is not safe.
599 *
600 * The above limitation is why this routine has the funny name
601 * mpol_fix_fork_child_flag().
602 *
603 * It is also safe to call this with a task pointer of current,
604 * which the static wrapper mpol_set_task_struct_flag() does,
605 * for use within this file.
606 */
607
608void mpol_fix_fork_child_flag(struct task_struct *p)
609{
610 if (p->mempolicy)
611 p->flags |= PF_MEMPOLICY;
612 else
613 p->flags &= ~PF_MEMPOLICY;
614}
615
616static void mpol_set_task_struct_flag(void)
617{
618 mpol_fix_fork_child_flag(current);
619}
620
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621/* Set the process memory policy */
David Rientjes028fec42008-04-28 02:12:25 -0700622static long do_set_mempolicy(unsigned short mode, unsigned short flags,
623 nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624{
Miao Xie58568d22009-06-16 15:31:49 -0700625 struct mempolicy *new, *old;
Lee Schermerhornf4e53d92008-04-28 02:13:10 -0700626 struct mm_struct *mm = current->mm;
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700627 NODEMASK_SCRATCH(scratch);
Miao Xie58568d22009-06-16 15:31:49 -0700628 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700630 if (!scratch)
631 return -ENOMEM;
Lee Schermerhornf4e53d92008-04-28 02:13:10 -0700632
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700633 new = mpol_new(mode, flags, nodes);
634 if (IS_ERR(new)) {
635 ret = PTR_ERR(new);
636 goto out;
637 }
Lee Schermerhornf4e53d92008-04-28 02:13:10 -0700638 /*
639 * prevent changing our mempolicy while show_numa_maps()
640 * is using it.
641 * Note: do_set_mempolicy() can be called at init time
642 * with no 'mm'.
643 */
644 if (mm)
645 down_write(&mm->mmap_sem);
Miao Xie58568d22009-06-16 15:31:49 -0700646 task_lock(current);
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700647 ret = mpol_set_nodemask(new, nodes, scratch);
Miao Xie58568d22009-06-16 15:31:49 -0700648 if (ret) {
649 task_unlock(current);
650 if (mm)
651 up_write(&mm->mmap_sem);
652 mpol_put(new);
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700653 goto out;
Miao Xie58568d22009-06-16 15:31:49 -0700654 }
655 old = current->mempolicy;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 current->mempolicy = new;
Paul Jacksonc61afb12006-03-24 03:16:08 -0800657 mpol_set_task_struct_flag();
Lee Schermerhorn45c47452008-04-28 02:13:12 -0700658 if (new && new->mode == MPOL_INTERLEAVE &&
David Rientjesf5b087b2008-04-28 02:12:27 -0700659 nodes_weight(new->v.nodes))
Andi Kleendfcd3c02005-10-29 18:15:48 -0700660 current->il_next = first_node(new->v.nodes);
Miao Xie58568d22009-06-16 15:31:49 -0700661 task_unlock(current);
Lee Schermerhornf4e53d92008-04-28 02:13:10 -0700662 if (mm)
663 up_write(&mm->mmap_sem);
664
Miao Xie58568d22009-06-16 15:31:49 -0700665 mpol_put(old);
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -0700666 ret = 0;
667out:
668 NODEMASK_SCRATCH_FREE(scratch);
669 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700670}
671
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700672/*
673 * Return nodemask for policy for get_mempolicy() query
Miao Xie58568d22009-06-16 15:31:49 -0700674 *
675 * Called with task's alloc_lock held
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700676 */
677static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678{
Andi Kleendfcd3c02005-10-29 18:15:48 -0700679 nodes_clear(*nodes);
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700680 if (p == &default_policy)
681 return;
682
Lee Schermerhorn45c47452008-04-28 02:13:12 -0700683 switch (p->mode) {
Mel Gorman19770b32008-04-28 02:12:18 -0700684 case MPOL_BIND:
685 /* Fall through */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 case MPOL_INTERLEAVE:
Andi Kleendfcd3c02005-10-29 18:15:48 -0700687 *nodes = p->v.nodes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 break;
689 case MPOL_PREFERRED:
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -0700690 if (!(p->flags & MPOL_F_LOCAL))
Andi Kleendfcd3c02005-10-29 18:15:48 -0700691 node_set(p->v.preferred_node, *nodes);
Lee Schermerhorn53f25562008-04-28 02:13:20 -0700692 /* else return empty node mask for local allocation */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693 break;
694 default:
695 BUG();
696 }
697}
698
699static int lookup_node(struct mm_struct *mm, unsigned long addr)
700{
701 struct page *p;
702 int err;
703
704 err = get_user_pages(current, mm, addr & PAGE_MASK, 1, 0, 0, &p, NULL);
705 if (err >= 0) {
706 err = page_to_nid(p);
707 put_page(p);
708 }
709 return err;
710}
711
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712/* Retrieve NUMA policy */
Adrian Bunkdbcb0f12007-10-16 01:26:26 -0700713static long do_get_mempolicy(int *policy, nodemask_t *nmask,
714 unsigned long addr, unsigned long flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715{
Christoph Lameter8bccd852005-10-29 18:16:59 -0700716 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 struct mm_struct *mm = current->mm;
718 struct vm_area_struct *vma = NULL;
719 struct mempolicy *pol = current->mempolicy;
720
Lee Schermerhorn754af6f2007-10-16 01:24:51 -0700721 if (flags &
722 ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700723 return -EINVAL;
Lee Schermerhorn754af6f2007-10-16 01:24:51 -0700724
725 if (flags & MPOL_F_MEMS_ALLOWED) {
726 if (flags & (MPOL_F_NODE|MPOL_F_ADDR))
727 return -EINVAL;
728 *policy = 0; /* just so it's initialized */
Miao Xie58568d22009-06-16 15:31:49 -0700729 task_lock(current);
Lee Schermerhorn754af6f2007-10-16 01:24:51 -0700730 *nmask = cpuset_current_mems_allowed;
Miao Xie58568d22009-06-16 15:31:49 -0700731 task_unlock(current);
Lee Schermerhorn754af6f2007-10-16 01:24:51 -0700732 return 0;
733 }
734
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735 if (flags & MPOL_F_ADDR) {
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700736 /*
737 * Do NOT fall back to task policy if the
738 * vma/shared policy at addr is NULL. We
739 * want to return MPOL_DEFAULT in this case.
740 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 down_read(&mm->mmap_sem);
742 vma = find_vma_intersection(mm, addr, addr+1);
743 if (!vma) {
744 up_read(&mm->mmap_sem);
745 return -EFAULT;
746 }
747 if (vma->vm_ops && vma->vm_ops->get_policy)
748 pol = vma->vm_ops->get_policy(vma, addr);
749 else
750 pol = vma->vm_policy;
751 } else if (addr)
752 return -EINVAL;
753
754 if (!pol)
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700755 pol = &default_policy; /* indicates default behavior */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756
757 if (flags & MPOL_F_NODE) {
758 if (flags & MPOL_F_ADDR) {
759 err = lookup_node(mm, addr);
760 if (err < 0)
761 goto out;
Christoph Lameter8bccd852005-10-29 18:16:59 -0700762 *policy = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 } else if (pol == current->mempolicy &&
Lee Schermerhorn45c47452008-04-28 02:13:12 -0700764 pol->mode == MPOL_INTERLEAVE) {
Christoph Lameter8bccd852005-10-29 18:16:59 -0700765 *policy = current->il_next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766 } else {
767 err = -EINVAL;
768 goto out;
769 }
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700770 } else {
771 *policy = pol == &default_policy ? MPOL_DEFAULT :
772 pol->mode;
David Rientjesd79df632008-07-04 12:24:13 -0700773 /*
774 * Internal mempolicy flags must be masked off before exposing
775 * the policy to userspace.
776 */
777 *policy |= (pol->flags & MPOL_MODE_FLAGS);
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700778 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779
780 if (vma) {
781 up_read(&current->mm->mmap_sem);
782 vma = NULL;
783 }
784
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 err = 0;
Miao Xie58568d22009-06-16 15:31:49 -0700786 if (nmask) {
787 task_lock(current);
Lee Schermerhornbea904d2008-04-28 02:13:18 -0700788 get_policy_nodemask(pol, nmask);
Miao Xie58568d22009-06-16 15:31:49 -0700789 task_unlock(current);
790 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791
792 out:
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -0700793 mpol_cond_put(pol);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 if (vma)
795 up_read(&current->mm->mmap_sem);
796 return err;
797}
798
Christoph Lameterb20a3502006-03-22 00:09:12 -0800799#ifdef CONFIG_MIGRATION
Christoph Lameter8bccd852005-10-29 18:16:59 -0700800/*
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800801 * page migration
802 */
Christoph Lameterfc301282006-01-18 17:42:29 -0800803static void migrate_page_add(struct page *page, struct list_head *pagelist,
804 unsigned long flags)
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800805{
806 /*
Christoph Lameterfc301282006-01-18 17:42:29 -0800807 * Avoid migrating a page that is shared with others.
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800808 */
Nick Piggin62695a82008-10-18 20:26:09 -0700809 if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1) {
810 if (!isolate_lru_page(page)) {
811 list_add_tail(&page->lru, pagelist);
812 }
813 }
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800814}
815
Christoph Lameter742755a2006-06-23 02:03:55 -0700816static struct page *new_node_page(struct page *page, unsigned long node, int **x)
Christoph Lameter95a402c2006-06-23 02:03:53 -0700817{
Mel Gorman6484eb32009-06-16 15:31:54 -0700818 return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0);
Christoph Lameter95a402c2006-06-23 02:03:53 -0700819}
820
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800821/*
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800822 * Migrate pages from one node to a target node.
823 * Returns error or the number of pages not migrated.
824 */
Adrian Bunkdbcb0f12007-10-16 01:26:26 -0700825static int migrate_to_node(struct mm_struct *mm, int source, int dest,
826 int flags)
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800827{
828 nodemask_t nmask;
829 LIST_HEAD(pagelist);
830 int err = 0;
831
832 nodes_clear(nmask);
833 node_set(source, nmask);
834
835 check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nmask,
836 flags | MPOL_MF_DISCONTIG_OK, &pagelist);
837
Christoph Lameteraaa994b2006-06-23 02:03:52 -0700838 if (!list_empty(&pagelist))
Christoph Lameter95a402c2006-06-23 02:03:53 -0700839 err = migrate_pages(&pagelist, new_node_page, dest);
840
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800841 return err;
842}
843
844/*
845 * Move pages between the two nodesets so as to preserve the physical
846 * layout as much as possible.
Christoph Lameter39743882006-01-08 01:00:51 -0800847 *
848 * Returns the number of page that could not be moved.
849 */
850int do_migrate_pages(struct mm_struct *mm,
851 const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
852{
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800853 int busy = 0;
Christoph Lameter0aedadf2008-11-06 12:53:30 -0800854 int err;
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800855 nodemask_t tmp;
Christoph Lameter39743882006-01-08 01:00:51 -0800856
Christoph Lameter0aedadf2008-11-06 12:53:30 -0800857 err = migrate_prep();
858 if (err)
859 return err;
860
Lee Schermerhorn53f25562008-04-28 02:13:20 -0700861 down_read(&mm->mmap_sem);
Christoph Lameter39743882006-01-08 01:00:51 -0800862
Christoph Lameter7b2259b2006-06-25 05:46:48 -0700863 err = migrate_vmas(mm, from_nodes, to_nodes, flags);
864 if (err)
865 goto out;
866
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800867/*
868 * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
869 * bit in 'to' is not also set in 'tmp'. Clear the found 'source'
870 * bit in 'tmp', and return that <source, dest> pair for migration.
871 * The pair of nodemasks 'to' and 'from' define the map.
872 *
873 * If no pair of bits is found that way, fallback to picking some
874 * pair of 'source' and 'dest' bits that are not the same. If the
875 * 'source' and 'dest' bits are the same, this represents a node
876 * that will be migrating to itself, so no pages need move.
877 *
878 * If no bits are left in 'tmp', or if all remaining bits left
879 * in 'tmp' correspond to the same bit in 'to', return false
880 * (nothing left to migrate).
881 *
882 * This lets us pick a pair of nodes to migrate between, such that
883 * if possible the dest node is not already occupied by some other
884 * source node, minimizing the risk of overloading the memory on a
885 * node that would happen if we migrated incoming memory to a node
886 * before migrating outgoing memory source that same node.
887 *
888 * A single scan of tmp is sufficient. As we go, we remember the
889 * most recent <s, d> pair that moved (s != d). If we find a pair
890 * that not only moved, but what's better, moved to an empty slot
891 * (d is not set in tmp), then we break out then, with that pair.
892 * Otherwise when we finish scannng from_tmp, we at least have the
893 * most recent <s, d> pair that moved. If we get all the way through
894 * the scan of tmp without finding any node that moved, much less
895 * moved to an empty node, then there is nothing left worth migrating.
896 */
Christoph Lameterd4984712006-01-08 01:00:55 -0800897
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800898 tmp = *from_nodes;
899 while (!nodes_empty(tmp)) {
900 int s,d;
901 int source = -1;
902 int dest = 0;
903
904 for_each_node_mask(s, tmp) {
905 d = node_remap(s, *from_nodes, *to_nodes);
906 if (s == d)
907 continue;
908
909 source = s; /* Node moved. Memorize */
910 dest = d;
911
912 /* dest not in remaining from nodes? */
913 if (!node_isset(dest, tmp))
914 break;
915 }
916 if (source == -1)
917 break;
918
919 node_clear(source, tmp);
920 err = migrate_to_node(mm, source, dest, flags);
921 if (err > 0)
922 busy += err;
923 if (err < 0)
924 break;
Christoph Lameter39743882006-01-08 01:00:51 -0800925 }
Christoph Lameter7b2259b2006-06-25 05:46:48 -0700926out:
Christoph Lameter39743882006-01-08 01:00:51 -0800927 up_read(&mm->mmap_sem);
Christoph Lameter7e2ab152006-02-01 03:05:40 -0800928 if (err < 0)
929 return err;
930 return busy;
Christoph Lameterb20a3502006-03-22 00:09:12 -0800931
Christoph Lameter39743882006-01-08 01:00:51 -0800932}
933
Lee Schermerhorn3ad33b22007-11-14 16:59:10 -0800934/*
935 * Allocate a new page for page migration based on vma policy.
936 * Start assuming that page is mapped by vma pointed to by @private.
937 * Search forward from there, if not. N.B., this assumes that the
938 * list of pages handed to migrate_pages()--which is how we get here--
939 * is in virtual address order.
940 */
Christoph Lameter742755a2006-06-23 02:03:55 -0700941static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
Christoph Lameter95a402c2006-06-23 02:03:53 -0700942{
943 struct vm_area_struct *vma = (struct vm_area_struct *)private;
Lee Schermerhorn3ad33b22007-11-14 16:59:10 -0800944 unsigned long uninitialized_var(address);
Christoph Lameter95a402c2006-06-23 02:03:53 -0700945
Lee Schermerhorn3ad33b22007-11-14 16:59:10 -0800946 while (vma) {
947 address = page_address_in_vma(page, vma);
948 if (address != -EFAULT)
949 break;
950 vma = vma->vm_next;
951 }
952
953 /*
954 * if !vma, alloc_page_vma() will use task or system default policy
955 */
956 return alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
Christoph Lameter95a402c2006-06-23 02:03:53 -0700957}
Christoph Lameterb20a3502006-03-22 00:09:12 -0800958#else
959
960static void migrate_page_add(struct page *page, struct list_head *pagelist,
961 unsigned long flags)
962{
963}
964
965int do_migrate_pages(struct mm_struct *mm,
966 const nodemask_t *from_nodes, const nodemask_t *to_nodes, int flags)
967{
968 return -ENOSYS;
969}
Christoph Lameter95a402c2006-06-23 02:03:53 -0700970
Keith Owens69939742006-10-11 01:21:28 -0700971static struct page *new_vma_page(struct page *page, unsigned long private, int **x)
Christoph Lameter95a402c2006-06-23 02:03:53 -0700972{
973 return NULL;
974}
Christoph Lameterb20a3502006-03-22 00:09:12 -0800975#endif
976
Adrian Bunkdbcb0f12007-10-16 01:26:26 -0700977static long do_mbind(unsigned long start, unsigned long len,
David Rientjes028fec42008-04-28 02:12:25 -0700978 unsigned short mode, unsigned short mode_flags,
979 nodemask_t *nmask, unsigned long flags)
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800980{
981 struct vm_area_struct *vma;
982 struct mm_struct *mm = current->mm;
983 struct mempolicy *new;
984 unsigned long end;
985 int err;
986 LIST_HEAD(pagelist);
987
David Rientjesa3b51e02008-04-28 02:12:23 -0700988 if (flags & ~(unsigned long)(MPOL_MF_STRICT |
989 MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800990 return -EINVAL;
Christoph Lameter74c00242006-03-14 19:50:21 -0800991 if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -0800992 return -EPERM;
993
994 if (start & ~PAGE_MASK)
995 return -EINVAL;
996
997 if (mode == MPOL_DEFAULT)
998 flags &= ~MPOL_MF_STRICT;
999
1000 len = (len + PAGE_SIZE - 1) & PAGE_MASK;
1001 end = start + len;
1002
1003 if (end < start)
1004 return -EINVAL;
1005 if (end == start)
1006 return 0;
1007
David Rientjes028fec42008-04-28 02:12:25 -07001008 new = mpol_new(mode, mode_flags, nmask);
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001009 if (IS_ERR(new))
1010 return PTR_ERR(new);
1011
1012 /*
1013 * If we are using the default policy then operation
1014 * on discontinuous address spaces is okay after all
1015 */
1016 if (!new)
1017 flags |= MPOL_MF_DISCONTIG_OK;
1018
David Rientjes028fec42008-04-28 02:12:25 -07001019 pr_debug("mbind %lx-%lx mode:%d flags:%d nodes:%lx\n",
1020 start, start + len, mode, mode_flags,
1021 nmask ? nodes_addr(*nmask)[0] : -1);
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001022
Christoph Lameter0aedadf2008-11-06 12:53:30 -08001023 if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) {
1024
1025 err = migrate_prep();
1026 if (err)
1027 return err;
1028 }
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001029 {
1030 NODEMASK_SCRATCH(scratch);
1031 if (scratch) {
1032 down_write(&mm->mmap_sem);
1033 task_lock(current);
1034 err = mpol_set_nodemask(new, nmask, scratch);
1035 task_unlock(current);
1036 if (err)
1037 up_write(&mm->mmap_sem);
1038 } else
1039 err = -ENOMEM;
1040 NODEMASK_SCRATCH_FREE(scratch);
1041 }
Miao Xie58568d22009-06-16 15:31:49 -07001042 if (err) {
Miao Xie58568d22009-06-16 15:31:49 -07001043 mpol_put(new);
1044 return err;
1045 }
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001046 vma = check_range(mm, start, end, nmask,
1047 flags | MPOL_MF_INVERT, &pagelist);
1048
1049 err = PTR_ERR(vma);
1050 if (!IS_ERR(vma)) {
1051 int nr_failed = 0;
1052
1053 err = mbind_range(vma, start, end, new);
Christoph Lameter7e2ab152006-02-01 03:05:40 -08001054
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001055 if (!list_empty(&pagelist))
Christoph Lameter95a402c2006-06-23 02:03:53 -07001056 nr_failed = migrate_pages(&pagelist, new_vma_page,
1057 (unsigned long)vma);
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001058
1059 if (!err && nr_failed && (flags & MPOL_MF_STRICT))
1060 err = -EIO;
1061 }
Christoph Lameterb20a3502006-03-22 00:09:12 -08001062
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001063 up_write(&mm->mmap_sem);
Lee Schermerhornf0be3d32008-04-28 02:13:08 -07001064 mpol_put(new);
Christoph Lameter6ce3c4c2006-01-08 01:01:04 -08001065 return err;
1066}
1067
Christoph Lameter39743882006-01-08 01:00:51 -08001068/*
Christoph Lameter8bccd852005-10-29 18:16:59 -07001069 * User space interface with variable sized bitmaps for nodelists.
1070 */
1071
1072/* Copy a node mask from user space. */
Christoph Lameter39743882006-01-08 01:00:51 -08001073static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask,
Christoph Lameter8bccd852005-10-29 18:16:59 -07001074 unsigned long maxnode)
1075{
1076 unsigned long k;
1077 unsigned long nlongs;
1078 unsigned long endmask;
1079
1080 --maxnode;
1081 nodes_clear(*nodes);
1082 if (maxnode == 0 || !nmask)
1083 return 0;
Andi Kleena9c930b2006-02-20 18:27:59 -08001084 if (maxnode > PAGE_SIZE*BITS_PER_BYTE)
Chris Wright636f13c2006-02-17 13:59:36 -08001085 return -EINVAL;
Christoph Lameter8bccd852005-10-29 18:16:59 -07001086
1087 nlongs = BITS_TO_LONGS(maxnode);
1088 if ((maxnode % BITS_PER_LONG) == 0)
1089 endmask = ~0UL;
1090 else
1091 endmask = (1UL << (maxnode % BITS_PER_LONG)) - 1;
1092
1093 /* When the user specified more nodes than supported just check
1094 if the non supported part is all zero. */
1095 if (nlongs > BITS_TO_LONGS(MAX_NUMNODES)) {
1096 if (nlongs > PAGE_SIZE/sizeof(long))
1097 return -EINVAL;
1098 for (k = BITS_TO_LONGS(MAX_NUMNODES); k < nlongs; k++) {
1099 unsigned long t;
1100 if (get_user(t, nmask + k))
1101 return -EFAULT;
1102 if (k == nlongs - 1) {
1103 if (t & endmask)
1104 return -EINVAL;
1105 } else if (t)
1106 return -EINVAL;
1107 }
1108 nlongs = BITS_TO_LONGS(MAX_NUMNODES);
1109 endmask = ~0UL;
1110 }
1111
1112 if (copy_from_user(nodes_addr(*nodes), nmask, nlongs*sizeof(unsigned long)))
1113 return -EFAULT;
1114 nodes_addr(*nodes)[nlongs-1] &= endmask;
1115 return 0;
1116}
1117
1118/* Copy a kernel node mask to user space */
1119static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode,
1120 nodemask_t *nodes)
1121{
1122 unsigned long copy = ALIGN(maxnode-1, 64) / 8;
1123 const int nbytes = BITS_TO_LONGS(MAX_NUMNODES) * sizeof(long);
1124
1125 if (copy > nbytes) {
1126 if (copy > PAGE_SIZE)
1127 return -EINVAL;
1128 if (clear_user((char __user *)mask + nbytes, copy - nbytes))
1129 return -EFAULT;
1130 copy = nbytes;
1131 }
1132 return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0;
1133}
1134
Heiko Carstens938bb9f2009-01-14 14:14:30 +01001135SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len,
1136 unsigned long, mode, unsigned long __user *, nmask,
1137 unsigned long, maxnode, unsigned, flags)
Christoph Lameter8bccd852005-10-29 18:16:59 -07001138{
1139 nodemask_t nodes;
1140 int err;
David Rientjes028fec42008-04-28 02:12:25 -07001141 unsigned short mode_flags;
Christoph Lameter8bccd852005-10-29 18:16:59 -07001142
David Rientjes028fec42008-04-28 02:12:25 -07001143 mode_flags = mode & MPOL_MODE_FLAGS;
1144 mode &= ~MPOL_MODE_FLAGS;
David Rientjesa3b51e02008-04-28 02:12:23 -07001145 if (mode >= MPOL_MAX)
1146 return -EINVAL;
David Rientjes4c50bc02008-04-28 02:12:30 -07001147 if ((mode_flags & MPOL_F_STATIC_NODES) &&
1148 (mode_flags & MPOL_F_RELATIVE_NODES))
1149 return -EINVAL;
Christoph Lameter8bccd852005-10-29 18:16:59 -07001150 err = get_nodes(&nodes, nmask, maxnode);
1151 if (err)
1152 return err;
David Rientjes028fec42008-04-28 02:12:25 -07001153 return do_mbind(start, len, mode, mode_flags, &nodes, flags);
Christoph Lameter8bccd852005-10-29 18:16:59 -07001154}
1155
1156/* Set the process memory policy */
Heiko Carstens938bb9f2009-01-14 14:14:30 +01001157SYSCALL_DEFINE3(set_mempolicy, int, mode, unsigned long __user *, nmask,
1158 unsigned long, maxnode)
Christoph Lameter8bccd852005-10-29 18:16:59 -07001159{
1160 int err;
1161 nodemask_t nodes;
David Rientjes028fec42008-04-28 02:12:25 -07001162 unsigned short flags;
Christoph Lameter8bccd852005-10-29 18:16:59 -07001163
David Rientjes028fec42008-04-28 02:12:25 -07001164 flags = mode & MPOL_MODE_FLAGS;
1165 mode &= ~MPOL_MODE_FLAGS;
1166 if ((unsigned int)mode >= MPOL_MAX)
Christoph Lameter8bccd852005-10-29 18:16:59 -07001167 return -EINVAL;
David Rientjes4c50bc02008-04-28 02:12:30 -07001168 if ((flags & MPOL_F_STATIC_NODES) && (flags & MPOL_F_RELATIVE_NODES))
1169 return -EINVAL;
Christoph Lameter8bccd852005-10-29 18:16:59 -07001170 err = get_nodes(&nodes, nmask, maxnode);
1171 if (err)
1172 return err;
David Rientjes028fec42008-04-28 02:12:25 -07001173 return do_set_mempolicy(mode, flags, &nodes);
Christoph Lameter8bccd852005-10-29 18:16:59 -07001174}
1175
Heiko Carstens938bb9f2009-01-14 14:14:30 +01001176SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode,
1177 const unsigned long __user *, old_nodes,
1178 const unsigned long __user *, new_nodes)
Christoph Lameter39743882006-01-08 01:00:51 -08001179{
David Howellsc69e8d92008-11-14 10:39:19 +11001180 const struct cred *cred = current_cred(), *tcred;
Christoph Lameter39743882006-01-08 01:00:51 -08001181 struct mm_struct *mm;
1182 struct task_struct *task;
1183 nodemask_t old;
1184 nodemask_t new;
1185 nodemask_t task_nodes;
1186 int err;
1187
1188 err = get_nodes(&old, old_nodes, maxnode);
1189 if (err)
1190 return err;
1191
1192 err = get_nodes(&new, new_nodes, maxnode);
1193 if (err)
1194 return err;
1195
1196 /* Find the mm_struct */
1197 read_lock(&tasklist_lock);
Pavel Emelyanov228ebcb2007-10-18 23:40:16 -07001198 task = pid ? find_task_by_vpid(pid) : current;
Christoph Lameter39743882006-01-08 01:00:51 -08001199 if (!task) {
1200 read_unlock(&tasklist_lock);
1201 return -ESRCH;
1202 }
1203 mm = get_task_mm(task);
1204 read_unlock(&tasklist_lock);
1205
1206 if (!mm)
1207 return -EINVAL;
1208
1209 /*
1210 * Check if this process has the right to modify the specified
1211 * process. The right exists if the process has administrative
Alexey Dobriyan7f927fc2006-03-28 01:56:53 -08001212 * capabilities, superuser privileges or the same
Christoph Lameter39743882006-01-08 01:00:51 -08001213 * userid as the target process.
1214 */
David Howellsc69e8d92008-11-14 10:39:19 +11001215 rcu_read_lock();
1216 tcred = __task_cred(task);
David Howellsb6dff3e2008-11-14 10:39:16 +11001217 if (cred->euid != tcred->suid && cred->euid != tcred->uid &&
1218 cred->uid != tcred->suid && cred->uid != tcred->uid &&
Christoph Lameter74c00242006-03-14 19:50:21 -08001219 !capable(CAP_SYS_NICE)) {
David Howellsc69e8d92008-11-14 10:39:19 +11001220 rcu_read_unlock();
Christoph Lameter39743882006-01-08 01:00:51 -08001221 err = -EPERM;
1222 goto out;
1223 }
David Howellsc69e8d92008-11-14 10:39:19 +11001224 rcu_read_unlock();
Christoph Lameter39743882006-01-08 01:00:51 -08001225
1226 task_nodes = cpuset_mems_allowed(task);
1227 /* Is the user allowed to access the target nodes? */
Christoph Lameter74c00242006-03-14 19:50:21 -08001228 if (!nodes_subset(new, task_nodes) && !capable(CAP_SYS_NICE)) {
Christoph Lameter39743882006-01-08 01:00:51 -08001229 err = -EPERM;
1230 goto out;
1231 }
1232
Lee Schermerhorn37b07e42007-10-16 01:25:39 -07001233 if (!nodes_subset(new, node_states[N_HIGH_MEMORY])) {
Christoph Lameter3b42d282007-08-31 00:12:08 -07001234 err = -EINVAL;
1235 goto out;
1236 }
1237
David Quigley86c3a762006-06-23 02:04:02 -07001238 err = security_task_movememory(task);
1239 if (err)
1240 goto out;
1241
Christoph Lameter511030b2006-02-28 16:58:57 -08001242 err = do_migrate_pages(mm, &old, &new,
Christoph Lameter74c00242006-03-14 19:50:21 -08001243 capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE);
Christoph Lameter39743882006-01-08 01:00:51 -08001244out:
1245 mmput(mm);
1246 return err;
1247}
1248
1249
Christoph Lameter8bccd852005-10-29 18:16:59 -07001250/* Retrieve NUMA policy */
Heiko Carstens938bb9f2009-01-14 14:14:30 +01001251SYSCALL_DEFINE5(get_mempolicy, int __user *, policy,
1252 unsigned long __user *, nmask, unsigned long, maxnode,
1253 unsigned long, addr, unsigned long, flags)
Christoph Lameter8bccd852005-10-29 18:16:59 -07001254{
Adrian Bunkdbcb0f12007-10-16 01:26:26 -07001255 int err;
1256 int uninitialized_var(pval);
Christoph Lameter8bccd852005-10-29 18:16:59 -07001257 nodemask_t nodes;
1258
1259 if (nmask != NULL && maxnode < MAX_NUMNODES)
1260 return -EINVAL;
1261
1262 err = do_get_mempolicy(&pval, &nodes, addr, flags);
1263
1264 if (err)
1265 return err;
1266
1267 if (policy && put_user(pval, policy))
1268 return -EFAULT;
1269
1270 if (nmask)
1271 err = copy_nodes_to_user(nmask, maxnode, &nodes);
1272
1273 return err;
1274}
1275
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276#ifdef CONFIG_COMPAT
1277
1278asmlinkage long compat_sys_get_mempolicy(int __user *policy,
1279 compat_ulong_t __user *nmask,
1280 compat_ulong_t maxnode,
1281 compat_ulong_t addr, compat_ulong_t flags)
1282{
1283 long err;
1284 unsigned long __user *nm = NULL;
1285 unsigned long nr_bits, alloc_size;
1286 DECLARE_BITMAP(bm, MAX_NUMNODES);
1287
1288 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
1289 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1290
1291 if (nmask)
1292 nm = compat_alloc_user_space(alloc_size);
1293
1294 err = sys_get_mempolicy(policy, nm, nr_bits+1, addr, flags);
1295
1296 if (!err && nmask) {
1297 err = copy_from_user(bm, nm, alloc_size);
1298 /* ensure entire bitmap is zeroed */
1299 err |= clear_user(nmask, ALIGN(maxnode-1, 8) / 8);
1300 err |= compat_put_bitmap(nmask, bm, nr_bits);
1301 }
1302
1303 return err;
1304}
1305
1306asmlinkage long compat_sys_set_mempolicy(int mode, compat_ulong_t __user *nmask,
1307 compat_ulong_t maxnode)
1308{
1309 long err = 0;
1310 unsigned long __user *nm = NULL;
1311 unsigned long nr_bits, alloc_size;
1312 DECLARE_BITMAP(bm, MAX_NUMNODES);
1313
1314 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
1315 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1316
1317 if (nmask) {
1318 err = compat_get_bitmap(bm, nmask, nr_bits);
1319 nm = compat_alloc_user_space(alloc_size);
1320 err |= copy_to_user(nm, bm, alloc_size);
1321 }
1322
1323 if (err)
1324 return -EFAULT;
1325
1326 return sys_set_mempolicy(mode, nm, nr_bits+1);
1327}
1328
1329asmlinkage long compat_sys_mbind(compat_ulong_t start, compat_ulong_t len,
1330 compat_ulong_t mode, compat_ulong_t __user *nmask,
1331 compat_ulong_t maxnode, compat_ulong_t flags)
1332{
1333 long err = 0;
1334 unsigned long __user *nm = NULL;
1335 unsigned long nr_bits, alloc_size;
Andi Kleendfcd3c02005-10-29 18:15:48 -07001336 nodemask_t bm;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337
1338 nr_bits = min_t(unsigned long, maxnode-1, MAX_NUMNODES);
1339 alloc_size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1340
1341 if (nmask) {
Andi Kleendfcd3c02005-10-29 18:15:48 -07001342 err = compat_get_bitmap(nodes_addr(bm), nmask, nr_bits);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001343 nm = compat_alloc_user_space(alloc_size);
Andi Kleendfcd3c02005-10-29 18:15:48 -07001344 err |= copy_to_user(nm, nodes_addr(bm), alloc_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001345 }
1346
1347 if (err)
1348 return -EFAULT;
1349
1350 return sys_mbind(start, len, mode, nm, nr_bits+1, flags);
1351}
1352
1353#endif
1354
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001355/*
1356 * get_vma_policy(@task, @vma, @addr)
1357 * @task - task for fallback if vma policy == default
1358 * @vma - virtual memory area whose policy is sought
1359 * @addr - address in @vma for shared policy lookup
1360 *
1361 * Returns effective policy for a VMA at specified address.
1362 * Falls back to @task or system default policy, as necessary.
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001363 * Current or other task's task mempolicy and non-shared vma policies
1364 * are protected by the task's mmap_sem, which must be held for read by
1365 * the caller.
1366 * Shared policies [those marked as MPOL_F_SHARED] require an extra reference
1367 * count--added by the get_policy() vm_op, as appropriate--to protect against
1368 * freeing by another task. It is the caller's responsibility to free the
1369 * extra reference for shared policies.
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001370 */
Lee Schermerhornae4d8c12008-04-28 02:13:11 -07001371static struct mempolicy *get_vma_policy(struct task_struct *task,
Christoph Lameter48fce342006-01-08 01:01:03 -08001372 struct vm_area_struct *vma, unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001373{
Christoph Lameter6e21c8f2005-09-03 15:54:45 -07001374 struct mempolicy *pol = task->mempolicy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001375
1376 if (vma) {
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001377 if (vma->vm_ops && vma->vm_ops->get_policy) {
Lee Schermerhornae4d8c12008-04-28 02:13:11 -07001378 struct mempolicy *vpol = vma->vm_ops->get_policy(vma,
1379 addr);
1380 if (vpol)
1381 pol = vpol;
Lee Schermerhornbea904d2008-04-28 02:13:18 -07001382 } else if (vma->vm_policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001383 pol = vma->vm_policy;
1384 }
1385 if (!pol)
1386 pol = &default_policy;
1387 return pol;
1388}
1389
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001390/*
1391 * Return a nodemask representing a mempolicy for filtering nodes for
1392 * page allocation
1393 */
1394static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy)
Mel Gorman19770b32008-04-28 02:12:18 -07001395{
1396 /* Lower zones don't get a nodemask applied for MPOL_BIND */
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001397 if (unlikely(policy->mode == MPOL_BIND) &&
Mel Gorman19770b32008-04-28 02:12:18 -07001398 gfp_zone(gfp) >= policy_zone &&
1399 cpuset_nodemask_valid_mems_allowed(&policy->v.nodes))
1400 return &policy->v.nodes;
1401
1402 return NULL;
1403}
1404
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001405/* Return a zonelist indicated by gfp for node representing a mempolicy */
1406static struct zonelist *policy_zonelist(gfp_t gfp, struct mempolicy *policy)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407{
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07001408 int nd = numa_node_id();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001409
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001410 switch (policy->mode) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001411 case MPOL_PREFERRED:
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07001412 if (!(policy->flags & MPOL_F_LOCAL))
1413 nd = policy->v.preferred_node;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001414 break;
1415 case MPOL_BIND:
Mel Gorman19770b32008-04-28 02:12:18 -07001416 /*
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001417 * Normally, MPOL_BIND allocations are node-local within the
1418 * allowed nodemask. However, if __GFP_THISNODE is set and the
1419 * current node is part of the mask, we use the zonelist for
1420 * the first node in the mask instead.
Mel Gorman19770b32008-04-28 02:12:18 -07001421 */
Mel Gorman19770b32008-04-28 02:12:18 -07001422 if (unlikely(gfp & __GFP_THISNODE) &&
1423 unlikely(!node_isset(nd, policy->v.nodes)))
1424 nd = first_node(policy->v.nodes);
1425 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001426 case MPOL_INTERLEAVE: /* should not happen */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001427 break;
1428 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429 BUG();
1430 }
Mel Gorman0e884602008-04-28 02:12:14 -07001431 return node_zonelist(nd, gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001432}
1433
1434/* Do dynamic interleaving for a process */
1435static unsigned interleave_nodes(struct mempolicy *policy)
1436{
1437 unsigned nid, next;
1438 struct task_struct *me = current;
1439
1440 nid = me->il_next;
Andi Kleendfcd3c02005-10-29 18:15:48 -07001441 next = next_node(nid, policy->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001442 if (next >= MAX_NUMNODES)
Andi Kleendfcd3c02005-10-29 18:15:48 -07001443 next = first_node(policy->v.nodes);
David Rientjesf5b087b2008-04-28 02:12:27 -07001444 if (next < MAX_NUMNODES)
1445 me->il_next = next;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446 return nid;
1447}
1448
Christoph Lameterdc85da12006-01-18 17:42:36 -08001449/*
1450 * Depending on the memory policy provide a node from which to allocate the
1451 * next slab entry.
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001452 * @policy must be protected by freeing by the caller. If @policy is
1453 * the current task's mempolicy, this protection is implicit, as only the
1454 * task can change it's policy. The system default policy requires no
1455 * such protection.
Christoph Lameterdc85da12006-01-18 17:42:36 -08001456 */
1457unsigned slab_node(struct mempolicy *policy)
1458{
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07001459 if (!policy || policy->flags & MPOL_F_LOCAL)
Lee Schermerhornbea904d2008-04-28 02:13:18 -07001460 return numa_node_id();
Christoph Lameter765c4502006-09-27 01:50:08 -07001461
Lee Schermerhornbea904d2008-04-28 02:13:18 -07001462 switch (policy->mode) {
1463 case MPOL_PREFERRED:
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07001464 /*
1465 * handled MPOL_F_LOCAL above
1466 */
1467 return policy->v.preferred_node;
Lee Schermerhornbea904d2008-04-28 02:13:18 -07001468
Christoph Lameterdc85da12006-01-18 17:42:36 -08001469 case MPOL_INTERLEAVE:
1470 return interleave_nodes(policy);
1471
Mel Gormandd1a2392008-04-28 02:12:17 -07001472 case MPOL_BIND: {
Christoph Lameterdc85da12006-01-18 17:42:36 -08001473 /*
1474 * Follow bind policy behavior and start allocation at the
1475 * first node.
1476 */
Mel Gorman19770b32008-04-28 02:12:18 -07001477 struct zonelist *zonelist;
1478 struct zone *zone;
1479 enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL);
1480 zonelist = &NODE_DATA(numa_node_id())->node_zonelists[0];
1481 (void)first_zones_zonelist(zonelist, highest_zoneidx,
1482 &policy->v.nodes,
1483 &zone);
1484 return zone->node;
Mel Gormandd1a2392008-04-28 02:12:17 -07001485 }
Christoph Lameterdc85da12006-01-18 17:42:36 -08001486
Christoph Lameterdc85da12006-01-18 17:42:36 -08001487 default:
Lee Schermerhornbea904d2008-04-28 02:13:18 -07001488 BUG();
Christoph Lameterdc85da12006-01-18 17:42:36 -08001489 }
1490}
1491
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492/* Do static interleaving for a VMA with known offset. */
1493static unsigned offset_il_node(struct mempolicy *pol,
1494 struct vm_area_struct *vma, unsigned long off)
1495{
Andi Kleendfcd3c02005-10-29 18:15:48 -07001496 unsigned nnodes = nodes_weight(pol->v.nodes);
David Rientjesf5b087b2008-04-28 02:12:27 -07001497 unsigned target;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 int c;
1499 int nid = -1;
1500
David Rientjesf5b087b2008-04-28 02:12:27 -07001501 if (!nnodes)
1502 return numa_node_id();
1503 target = (unsigned int)off % nnodes;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504 c = 0;
1505 do {
Andi Kleendfcd3c02005-10-29 18:15:48 -07001506 nid = next_node(nid, pol->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001507 c++;
1508 } while (c <= target);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001509 return nid;
1510}
1511
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001512/* Determine a node number for interleave */
1513static inline unsigned interleave_nid(struct mempolicy *pol,
1514 struct vm_area_struct *vma, unsigned long addr, int shift)
1515{
1516 if (vma) {
1517 unsigned long off;
1518
Nishanth Aravamudan3b98b082006-08-31 21:27:53 -07001519 /*
1520 * for small pages, there is no difference between
1521 * shift and PAGE_SHIFT, so the bit-shift is safe.
1522 * for huge pages, since vm_pgoff is in units of small
1523 * pages, we need to shift off the always 0 bits to get
1524 * a useful offset.
1525 */
1526 BUG_ON(shift < PAGE_SHIFT);
1527 off = vma->vm_pgoff >> (shift - PAGE_SHIFT);
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001528 off += (addr - vma->vm_start) >> shift;
1529 return offset_il_node(pol, vma, off);
1530 } else
1531 return interleave_nodes(pol);
1532}
1533
Chen, Kenneth W00ac59a2006-02-03 21:51:14 +01001534#ifdef CONFIG_HUGETLBFS
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001535/*
1536 * huge_zonelist(@vma, @addr, @gfp_flags, @mpol)
1537 * @vma = virtual memory area whose policy is sought
1538 * @addr = address in @vma for shared policy lookup and interleave policy
1539 * @gfp_flags = for requested zone
Mel Gorman19770b32008-04-28 02:12:18 -07001540 * @mpol = pointer to mempolicy pointer for reference counted mempolicy
1541 * @nodemask = pointer to nodemask pointer for MPOL_BIND nodemask
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001542 *
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001543 * Returns a zonelist suitable for a huge page allocation and a pointer
1544 * to the struct mempolicy for conditional unref after allocation.
1545 * If the effective policy is 'BIND, returns a pointer to the mempolicy's
1546 * @nodemask for filtering the zonelist.
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001547 */
Mel Gorman396faf02007-07-17 04:03:13 -07001548struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,
Mel Gorman19770b32008-04-28 02:12:18 -07001549 gfp_t gfp_flags, struct mempolicy **mpol,
1550 nodemask_t **nodemask)
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001551{
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001552 struct zonelist *zl;
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001553
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001554 *mpol = get_vma_policy(current, vma, addr);
Mel Gorman19770b32008-04-28 02:12:18 -07001555 *nodemask = NULL; /* assume !MPOL_BIND */
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001556
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001557 if (unlikely((*mpol)->mode == MPOL_INTERLEAVE)) {
1558 zl = node_zonelist(interleave_nid(*mpol, vma, addr,
Andi Kleena5516432008-07-23 21:27:41 -07001559 huge_page_shift(hstate_vma(vma))), gfp_flags);
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001560 } else {
1561 zl = policy_zonelist(gfp_flags, *mpol);
1562 if ((*mpol)->mode == MPOL_BIND)
1563 *nodemask = &(*mpol)->v.nodes;
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001564 }
1565 return zl;
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001566}
Chen, Kenneth W00ac59a2006-02-03 21:51:14 +01001567#endif
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001568
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569/* Allocate a page in interleaved policy.
1570 Own path because it needs to do special accounting. */
Andi Kleen662f3a02005-10-29 18:15:49 -07001571static struct page *alloc_page_interleave(gfp_t gfp, unsigned order,
1572 unsigned nid)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573{
1574 struct zonelist *zl;
1575 struct page *page;
1576
Mel Gorman0e884602008-04-28 02:12:14 -07001577 zl = node_zonelist(nid, gfp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001578 page = __alloc_pages(gfp, order, zl);
Mel Gormandd1a2392008-04-28 02:12:17 -07001579 if (page && page_zone(page) == zonelist_zone(&zl->_zonerefs[0]))
Christoph Lameterca889e62006-06-30 01:55:44 -07001580 inc_zone_page_state(page, NUMA_INTERLEAVE_HIT);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001581 return page;
1582}
1583
1584/**
1585 * alloc_page_vma - Allocate a page for a VMA.
1586 *
1587 * @gfp:
1588 * %GFP_USER user allocation.
1589 * %GFP_KERNEL kernel allocations,
1590 * %GFP_HIGHMEM highmem/user allocations,
1591 * %GFP_FS allocation should not call back into a file system.
1592 * %GFP_ATOMIC don't sleep.
1593 *
1594 * @vma: Pointer to VMA or NULL if not available.
1595 * @addr: Virtual Address of the allocation. Must be inside the VMA.
1596 *
1597 * This function allocates a page from the kernel page pool and applies
1598 * a NUMA policy associated with the VMA or the current process.
1599 * When VMA is not NULL caller must hold down_read on the mmap_sem of the
1600 * mm_struct of the VMA to prevent it from going away. Should be used for
1601 * all allocations for pages that will be mapped into
1602 * user space. Returns NULL when no page can be allocated.
1603 *
1604 * Should be called with the mm_sem of the vma hold.
1605 */
1606struct page *
Al Virodd0fc662005-10-07 07:46:04 +01001607alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001608{
Christoph Lameter6e21c8f2005-09-03 15:54:45 -07001609 struct mempolicy *pol = get_vma_policy(current, vma, addr);
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001610 struct zonelist *zl;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001611
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001612 if (unlikely(pol->mode == MPOL_INTERLEAVE)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001613 unsigned nid;
Christoph Lameter5da7ca82006-01-06 00:10:46 -08001614
1615 nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001616 mpol_cond_put(pol);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001617 return alloc_page_interleave(gfp, 0, nid);
1618 }
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001619 zl = policy_zonelist(gfp, pol);
1620 if (unlikely(mpol_needs_cond_ref(pol))) {
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001621 /*
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001622 * slow path: ref counted shared policy
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001623 */
Mel Gorman19770b32008-04-28 02:12:18 -07001624 struct page *page = __alloc_pages_nodemask(gfp, 0,
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001625 zl, policy_nodemask(gfp, pol));
Lee Schermerhornf0be3d32008-04-28 02:13:08 -07001626 __mpol_put(pol);
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07001627 return page;
1628 }
1629 /*
1630 * fast path: default or task policy
1631 */
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001632 return __alloc_pages_nodemask(gfp, 0, zl, policy_nodemask(gfp, pol));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001633}
1634
1635/**
1636 * alloc_pages_current - Allocate pages.
1637 *
1638 * @gfp:
1639 * %GFP_USER user allocation,
1640 * %GFP_KERNEL kernel allocation,
1641 * %GFP_HIGHMEM highmem allocation,
1642 * %GFP_FS don't call back into a file system.
1643 * %GFP_ATOMIC don't sleep.
1644 * @order: Power of two of allocation size in pages. 0 is a single page.
1645 *
1646 * Allocate a page from the kernel page pool. When not in
1647 * interrupt context and apply the current process NUMA policy.
1648 * Returns NULL when no page can be allocated.
1649 *
Paul Jacksoncf2a473c2006-01-08 01:01:54 -08001650 * Don't call cpuset_update_task_memory_state() unless
Linus Torvalds1da177e2005-04-16 15:20:36 -07001651 * 1) it's ok to take cpuset_sem (can WAIT), and
1652 * 2) allocating for current task (not interrupt).
1653 */
Al Virodd0fc662005-10-07 07:46:04 +01001654struct page *alloc_pages_current(gfp_t gfp, unsigned order)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001655{
1656 struct mempolicy *pol = current->mempolicy;
1657
Christoph Lameter9b819d22006-09-25 23:31:40 -07001658 if (!pol || in_interrupt() || (gfp & __GFP_THISNODE))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001659 pol = &default_policy;
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001660
1661 /*
1662 * No reference counting needed for current->mempolicy
1663 * nor system default_policy
1664 */
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001665 if (pol->mode == MPOL_INTERLEAVE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 return alloc_page_interleave(gfp, order, interleave_nodes(pol));
Mel Gorman19770b32008-04-28 02:12:18 -07001667 return __alloc_pages_nodemask(gfp, order,
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001668 policy_zonelist(gfp, pol), policy_nodemask(gfp, pol));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669}
1670EXPORT_SYMBOL(alloc_pages_current);
1671
Paul Jackson42253992006-01-08 01:01:59 -08001672/*
Lee Schermerhorn846a16b2008-04-28 02:13:09 -07001673 * If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it
Paul Jackson42253992006-01-08 01:01:59 -08001674 * rebinds the mempolicy its copying by calling mpol_rebind_policy()
1675 * with the mems_allowed returned by cpuset_mems_allowed(). This
1676 * keeps mempolicies cpuset relative after its cpuset moves. See
1677 * further kernel/cpuset.c update_nodemask().
1678 */
Paul Jackson42253992006-01-08 01:01:59 -08001679
Lee Schermerhorn846a16b2008-04-28 02:13:09 -07001680/* Slow path of a mempolicy duplicate */
1681struct mempolicy *__mpol_dup(struct mempolicy *old)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001682{
1683 struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL);
1684
1685 if (!new)
1686 return ERR_PTR(-ENOMEM);
Paul Jackson42253992006-01-08 01:01:59 -08001687 if (current_cpuset_is_being_rebound()) {
1688 nodemask_t mems = cpuset_mems_allowed(current);
1689 mpol_rebind_policy(old, &mems);
1690 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001691 *new = *old;
1692 atomic_set(&new->refcnt, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001693 return new;
1694}
1695
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07001696/*
1697 * If *frompol needs [has] an extra ref, copy *frompol to *tompol ,
1698 * eliminate the * MPOL_F_* flags that require conditional ref and
1699 * [NOTE!!!] drop the extra ref. Not safe to reference *frompol directly
1700 * after return. Use the returned value.
1701 *
1702 * Allows use of a mempolicy for, e.g., multiple allocations with a single
1703 * policy lookup, even if the policy needs/has extra ref on lookup.
1704 * shmem_readahead needs this.
1705 */
1706struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol,
1707 struct mempolicy *frompol)
1708{
1709 if (!mpol_needs_cond_ref(frompol))
1710 return frompol;
1711
1712 *tompol = *frompol;
1713 tompol->flags &= ~MPOL_F_SHARED; /* copy doesn't need unref */
1714 __mpol_put(frompol);
1715 return tompol;
1716}
1717
David Rientjesf5b087b2008-04-28 02:12:27 -07001718static int mpol_match_intent(const struct mempolicy *a,
1719 const struct mempolicy *b)
1720{
1721 if (a->flags != b->flags)
1722 return 0;
1723 if (!mpol_store_user_nodemask(a))
1724 return 1;
1725 return nodes_equal(a->w.user_nodemask, b->w.user_nodemask);
1726}
1727
Linus Torvalds1da177e2005-04-16 15:20:36 -07001728/* Slow path of a mempolicy comparison */
1729int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
1730{
1731 if (!a || !b)
1732 return 0;
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001733 if (a->mode != b->mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001734 return 0;
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001735 if (a->mode != MPOL_DEFAULT && !mpol_match_intent(a, b))
David Rientjesf5b087b2008-04-28 02:12:27 -07001736 return 0;
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001737 switch (a->mode) {
Mel Gorman19770b32008-04-28 02:12:18 -07001738 case MPOL_BIND:
1739 /* Fall through */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001740 case MPOL_INTERLEAVE:
Andi Kleendfcd3c02005-10-29 18:15:48 -07001741 return nodes_equal(a->v.nodes, b->v.nodes);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001742 case MPOL_PREFERRED:
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07001743 return a->v.preferred_node == b->v.preferred_node &&
1744 a->flags == b->flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001745 default:
1746 BUG();
1747 return 0;
1748 }
1749}
1750
Linus Torvalds1da177e2005-04-16 15:20:36 -07001751/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001752 * Shared memory backing store policy support.
1753 *
1754 * Remember policies even when nobody has shared memory mapped.
1755 * The policies are kept in Red-Black tree linked from the inode.
1756 * They are protected by the sp->lock spinlock, which should be held
1757 * for any accesses to the tree.
1758 */
1759
1760/* lookup first element intersecting start-end */
1761/* Caller holds sp->lock */
1762static struct sp_node *
1763sp_lookup(struct shared_policy *sp, unsigned long start, unsigned long end)
1764{
1765 struct rb_node *n = sp->root.rb_node;
1766
1767 while (n) {
1768 struct sp_node *p = rb_entry(n, struct sp_node, nd);
1769
1770 if (start >= p->end)
1771 n = n->rb_right;
1772 else if (end <= p->start)
1773 n = n->rb_left;
1774 else
1775 break;
1776 }
1777 if (!n)
1778 return NULL;
1779 for (;;) {
1780 struct sp_node *w = NULL;
1781 struct rb_node *prev = rb_prev(n);
1782 if (!prev)
1783 break;
1784 w = rb_entry(prev, struct sp_node, nd);
1785 if (w->end <= start)
1786 break;
1787 n = prev;
1788 }
1789 return rb_entry(n, struct sp_node, nd);
1790}
1791
1792/* Insert a new shared policy into the list. */
1793/* Caller holds sp->lock */
1794static void sp_insert(struct shared_policy *sp, struct sp_node *new)
1795{
1796 struct rb_node **p = &sp->root.rb_node;
1797 struct rb_node *parent = NULL;
1798 struct sp_node *nd;
1799
1800 while (*p) {
1801 parent = *p;
1802 nd = rb_entry(parent, struct sp_node, nd);
1803 if (new->start < nd->start)
1804 p = &(*p)->rb_left;
1805 else if (new->end > nd->end)
1806 p = &(*p)->rb_right;
1807 else
1808 BUG();
1809 }
1810 rb_link_node(&new->nd, parent, p);
1811 rb_insert_color(&new->nd, &sp->root);
Paul Mundt140d5a42007-07-15 23:38:16 -07001812 pr_debug("inserting %lx-%lx: %d\n", new->start, new->end,
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001813 new->policy ? new->policy->mode : 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001814}
1815
1816/* Find shared policy intersecting idx */
1817struct mempolicy *
1818mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
1819{
1820 struct mempolicy *pol = NULL;
1821 struct sp_node *sn;
1822
1823 if (!sp->root.rb_node)
1824 return NULL;
1825 spin_lock(&sp->lock);
1826 sn = sp_lookup(sp, idx, idx+1);
1827 if (sn) {
1828 mpol_get(sn->policy);
1829 pol = sn->policy;
1830 }
1831 spin_unlock(&sp->lock);
1832 return pol;
1833}
1834
1835static void sp_delete(struct shared_policy *sp, struct sp_node *n)
1836{
Paul Mundt140d5a42007-07-15 23:38:16 -07001837 pr_debug("deleting %lx-l%lx\n", n->start, n->end);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001838 rb_erase(&n->nd, &sp->root);
Lee Schermerhornf0be3d32008-04-28 02:13:08 -07001839 mpol_put(n->policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001840 kmem_cache_free(sn_cache, n);
1841}
1842
Adrian Bunkdbcb0f12007-10-16 01:26:26 -07001843static struct sp_node *sp_alloc(unsigned long start, unsigned long end,
1844 struct mempolicy *pol)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001845{
1846 struct sp_node *n = kmem_cache_alloc(sn_cache, GFP_KERNEL);
1847
1848 if (!n)
1849 return NULL;
1850 n->start = start;
1851 n->end = end;
1852 mpol_get(pol);
Lee Schermerhornaab0b102008-04-28 02:13:13 -07001853 pol->flags |= MPOL_F_SHARED; /* for unref */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001854 n->policy = pol;
1855 return n;
1856}
1857
1858/* Replace a policy range. */
1859static int shared_policy_replace(struct shared_policy *sp, unsigned long start,
1860 unsigned long end, struct sp_node *new)
1861{
1862 struct sp_node *n, *new2 = NULL;
1863
1864restart:
1865 spin_lock(&sp->lock);
1866 n = sp_lookup(sp, start, end);
1867 /* Take care of old policies in the same range. */
1868 while (n && n->start < end) {
1869 struct rb_node *next = rb_next(&n->nd);
1870 if (n->start >= start) {
1871 if (n->end <= end)
1872 sp_delete(sp, n);
1873 else
1874 n->start = end;
1875 } else {
1876 /* Old policy spanning whole new range. */
1877 if (n->end > end) {
1878 if (!new2) {
1879 spin_unlock(&sp->lock);
1880 new2 = sp_alloc(end, n->end, n->policy);
1881 if (!new2)
1882 return -ENOMEM;
1883 goto restart;
1884 }
1885 n->end = start;
1886 sp_insert(sp, new2);
1887 new2 = NULL;
1888 break;
1889 } else
1890 n->end = start;
1891 }
1892 if (!next)
1893 break;
1894 n = rb_entry(next, struct sp_node, nd);
1895 }
1896 if (new)
1897 sp_insert(sp, new);
1898 spin_unlock(&sp->lock);
1899 if (new2) {
Lee Schermerhornf0be3d32008-04-28 02:13:08 -07001900 mpol_put(new2->policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001901 kmem_cache_free(sn_cache, new2);
1902 }
1903 return 0;
1904}
1905
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001906/**
1907 * mpol_shared_policy_init - initialize shared policy for inode
1908 * @sp: pointer to inode shared policy
1909 * @mpol: struct mempolicy to install
1910 *
1911 * Install non-NULL @mpol in inode's shared policy rb-tree.
1912 * On entry, the current task has a reference on a non-NULL @mpol.
1913 * This must be released on exit.
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001914 * This is called at get_inode() calls and we can use GFP_KERNEL.
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001915 */
1916void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
Robin Holt7339ff82006-01-14 13:20:48 -08001917{
Miao Xie58568d22009-06-16 15:31:49 -07001918 int ret;
1919
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001920 sp->root = RB_ROOT; /* empty tree == default mempolicy */
1921 spin_lock_init(&sp->lock);
Robin Holt7339ff82006-01-14 13:20:48 -08001922
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001923 if (mpol) {
1924 struct vm_area_struct pvma;
1925 struct mempolicy *new;
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001926 NODEMASK_SCRATCH(scratch);
Robin Holt7339ff82006-01-14 13:20:48 -08001927
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001928 if (!scratch)
1929 return;
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001930 /* contextualize the tmpfs mount point mempolicy */
1931 new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
Miao Xie58568d22009-06-16 15:31:49 -07001932 if (IS_ERR(new)) {
1933 mpol_put(mpol); /* drop our ref on sb mpol */
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001934 NODEMASK_SCRATCH_FREE(scratch);
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001935 return; /* no valid nodemask intersection */
Miao Xie58568d22009-06-16 15:31:49 -07001936 }
1937
1938 task_lock(current);
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001939 ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch);
Miao Xie58568d22009-06-16 15:31:49 -07001940 task_unlock(current);
1941 mpol_put(mpol); /* drop our ref on sb mpol */
1942 if (ret) {
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001943 NODEMASK_SCRATCH_FREE(scratch);
Miao Xie58568d22009-06-16 15:31:49 -07001944 mpol_put(new);
1945 return;
1946 }
Robin Holt7339ff82006-01-14 13:20:48 -08001947
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07001948 /* Create pseudo-vma that contains just the policy */
1949 memset(&pvma, 0, sizeof(struct vm_area_struct));
1950 pvma.vm_end = TASK_SIZE; /* policy covers entire file */
1951 mpol_set_shared_policy(sp, &pvma, new); /* adds ref */
1952 mpol_put(new); /* drop initial ref */
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07001953 NODEMASK_SCRATCH_FREE(scratch);
Robin Holt7339ff82006-01-14 13:20:48 -08001954 }
1955}
1956
Linus Torvalds1da177e2005-04-16 15:20:36 -07001957int mpol_set_shared_policy(struct shared_policy *info,
1958 struct vm_area_struct *vma, struct mempolicy *npol)
1959{
1960 int err;
1961 struct sp_node *new = NULL;
1962 unsigned long sz = vma_pages(vma);
1963
David Rientjes028fec42008-04-28 02:12:25 -07001964 pr_debug("set_shared_policy %lx sz %lu %d %d %lx\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001965 vma->vm_pgoff,
Lee Schermerhorn45c47452008-04-28 02:13:12 -07001966 sz, npol ? npol->mode : -1,
David Rientjes028fec42008-04-28 02:12:25 -07001967 npol ? npol->flags : -1,
Paul Mundt140d5a42007-07-15 23:38:16 -07001968 npol ? nodes_addr(npol->v.nodes)[0] : -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969
1970 if (npol) {
1971 new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol);
1972 if (!new)
1973 return -ENOMEM;
1974 }
1975 err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new);
1976 if (err && new)
1977 kmem_cache_free(sn_cache, new);
1978 return err;
1979}
1980
1981/* Free a backing policy store on inode delete. */
1982void mpol_free_shared_policy(struct shared_policy *p)
1983{
1984 struct sp_node *n;
1985 struct rb_node *next;
1986
1987 if (!p->root.rb_node)
1988 return;
1989 spin_lock(&p->lock);
1990 next = rb_first(&p->root);
1991 while (next) {
1992 n = rb_entry(next, struct sp_node, nd);
1993 next = rb_next(&n->nd);
Andi Kleen90c50292005-07-27 11:43:50 -07001994 rb_erase(&n->nd, &p->root);
Lee Schermerhornf0be3d32008-04-28 02:13:08 -07001995 mpol_put(n->policy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001996 kmem_cache_free(sn_cache, n);
1997 }
1998 spin_unlock(&p->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001999}
2000
2001/* assumes fs == KERNEL_DS */
2002void __init numa_policy_init(void)
2003{
Paul Mundtb71636e2007-07-15 23:38:15 -07002004 nodemask_t interleave_nodes;
2005 unsigned long largest = 0;
2006 int nid, prefer = 0;
2007
Linus Torvalds1da177e2005-04-16 15:20:36 -07002008 policy_cache = kmem_cache_create("numa_policy",
2009 sizeof(struct mempolicy),
Paul Mundt20c2df82007-07-20 10:11:58 +09002010 0, SLAB_PANIC, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002011
2012 sn_cache = kmem_cache_create("shared_policy_node",
2013 sizeof(struct sp_node),
Paul Mundt20c2df82007-07-20 10:11:58 +09002014 0, SLAB_PANIC, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002015
Paul Mundtb71636e2007-07-15 23:38:15 -07002016 /*
2017 * Set interleaving policy for system init. Interleaving is only
2018 * enabled across suitably sized nodes (default is >= 16MB), or
2019 * fall back to the largest node if they're all smaller.
2020 */
2021 nodes_clear(interleave_nodes);
Christoph Lameter56bbd652007-10-16 01:25:35 -07002022 for_each_node_state(nid, N_HIGH_MEMORY) {
Paul Mundtb71636e2007-07-15 23:38:15 -07002023 unsigned long total_pages = node_present_pages(nid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002024
Paul Mundtb71636e2007-07-15 23:38:15 -07002025 /* Preserve the largest node */
2026 if (largest < total_pages) {
2027 largest = total_pages;
2028 prefer = nid;
2029 }
2030
2031 /* Interleave this node? */
2032 if ((total_pages << PAGE_SHIFT) >= (16 << 20))
2033 node_set(nid, interleave_nodes);
2034 }
2035
2036 /* All too small, use the largest */
2037 if (unlikely(nodes_empty(interleave_nodes)))
2038 node_set(prefer, interleave_nodes);
2039
David Rientjes028fec42008-04-28 02:12:25 -07002040 if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002041 printk("numa_policy_init: interleaving failed\n");
2042}
2043
Christoph Lameter8bccd852005-10-29 18:16:59 -07002044/* Reset policy of current process to default */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002045void numa_default_policy(void)
2046{
David Rientjes028fec42008-04-28 02:12:25 -07002047 do_set_mempolicy(MPOL_DEFAULT, 0, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002048}
Paul Jackson68860ec2005-10-30 15:02:36 -08002049
Paul Jackson42253992006-01-08 01:01:59 -08002050/*
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002051 * Parse and format mempolicy from/to strings
2052 */
2053
2054/*
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07002055 * "local" is pseudo-policy: MPOL_PREFERRED with MPOL_F_LOCAL flag
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002056 * Used only for mpol_parse_str() and mpol_to_str()
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002057 */
Lee Schermerhorn53f25562008-04-28 02:13:20 -07002058#define MPOL_LOCAL (MPOL_INTERLEAVE + 1)
Helge Deller15ad7cd2006-12-06 20:40:36 -08002059static const char * const policy_types[] =
Lee Schermerhorn53f25562008-04-28 02:13:20 -07002060 { "default", "prefer", "bind", "interleave", "local" };
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002061
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002062
2063#ifdef CONFIG_TMPFS
2064/**
2065 * mpol_parse_str - parse string to mempolicy
2066 * @str: string containing mempolicy to parse
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002067 * @mpol: pointer to struct mempolicy pointer, returned on success.
2068 * @no_context: flag whether to "contextualize" the mempolicy
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002069 *
2070 * Format of input:
2071 * <mode>[=<flags>][:<nodelist>]
2072 *
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002073 * if @no_context is true, save the input nodemask in w.user_nodemask in
2074 * the returned mempolicy. This will be used to "clone" the mempolicy in
2075 * a specific context [cpuset] at a later time. Used to parse tmpfs mpol
2076 * mount option. Note that if 'static' or 'relative' mode flags were
2077 * specified, the input nodemask will already have been saved. Saving
2078 * it again is redundant, but safe.
2079 *
2080 * On success, returns 0, else 1
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002081 */
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002082int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002083{
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002084 struct mempolicy *new = NULL;
2085 unsigned short uninitialized_var(mode);
2086 unsigned short uninitialized_var(mode_flags);
2087 nodemask_t nodes;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002088 char *nodelist = strchr(str, ':');
2089 char *flags = strchr(str, '=');
2090 int i;
2091 int err = 1;
2092
2093 if (nodelist) {
2094 /* NUL-terminate mode or flags string */
2095 *nodelist++ = '\0';
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002096 if (nodelist_parse(nodelist, nodes))
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002097 goto out;
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002098 if (!nodes_subset(nodes, node_states[N_HIGH_MEMORY]))
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002099 goto out;
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002100 } else
2101 nodes_clear(nodes);
2102
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002103 if (flags)
2104 *flags++ = '\0'; /* terminate mode string */
2105
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002106 for (i = 0; i <= MPOL_LOCAL; i++) {
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002107 if (!strcmp(str, policy_types[i])) {
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002108 mode = i;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002109 break;
2110 }
2111 }
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002112 if (i > MPOL_LOCAL)
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002113 goto out;
2114
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002115 switch (mode) {
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002116 case MPOL_PREFERRED:
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002117 /*
2118 * Insist on a nodelist of one node only
2119 */
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002120 if (nodelist) {
2121 char *rest = nodelist;
2122 while (isdigit(*rest))
2123 rest++;
2124 if (!*rest)
2125 err = 0;
2126 }
2127 break;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002128 case MPOL_INTERLEAVE:
2129 /*
2130 * Default to online nodes with memory if no nodelist
2131 */
2132 if (!nodelist)
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002133 nodes = node_states[N_HIGH_MEMORY];
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002134 err = 0;
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002135 break;
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002136 case MPOL_LOCAL:
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002137 /*
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002138 * Don't allow a nodelist; mpol_new() checks flags
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002139 */
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002140 if (nodelist)
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002141 goto out;
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002142 mode = MPOL_PREFERRED;
Lee Schermerhorn3f226aa2008-04-28 02:13:24 -07002143 break;
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002144
2145 /*
2146 * case MPOL_BIND: mpol_new() enforces non-empty nodemask.
2147 * case MPOL_DEFAULT: mpol_new() enforces empty nodemask, ignores flags.
2148 */
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002149 }
2150
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002151 mode_flags = 0;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002152 if (flags) {
2153 /*
2154 * Currently, we only support two mutually exclusive
2155 * mode flags.
2156 */
2157 if (!strcmp(flags, "static"))
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002158 mode_flags |= MPOL_F_STATIC_NODES;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002159 else if (!strcmp(flags, "relative"))
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002160 mode_flags |= MPOL_F_RELATIVE_NODES;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002161 else
2162 err = 1;
2163 }
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002164
2165 new = mpol_new(mode, mode_flags, &nodes);
2166 if (IS_ERR(new))
2167 err = 1;
Miao Xie58568d22009-06-16 15:31:49 -07002168 else {
2169 int ret;
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07002170 NODEMASK_SCRATCH(scratch);
2171 if (scratch) {
2172 task_lock(current);
2173 ret = mpol_set_nodemask(new, &nodes, scratch);
2174 task_unlock(current);
2175 } else
2176 ret = -ENOMEM;
2177 NODEMASK_SCRATCH_FREE(scratch);
2178 if (ret) {
Miao Xie58568d22009-06-16 15:31:49 -07002179 err = 1;
KAMEZAWA Hiroyuki4bfc4492009-08-06 15:07:33 -07002180 mpol_put(new);
2181 } else if (no_context) {
Miao Xie58568d22009-06-16 15:31:49 -07002182 /* save for contextualization */
2183 new->w.user_nodemask = nodes;
2184 }
2185 }
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002186
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002187out:
2188 /* Restore string for error message */
2189 if (nodelist)
2190 *--nodelist = ':';
2191 if (flags)
2192 *--flags = '=';
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002193 if (!err)
2194 *mpol = new;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002195 return err;
2196}
2197#endif /* CONFIG_TMPFS */
2198
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002199/**
2200 * mpol_to_str - format a mempolicy structure for printing
2201 * @buffer: to contain formatted mempolicy string
2202 * @maxlen: length of @buffer
2203 * @pol: pointer to mempolicy to be formatted
2204 * @no_context: "context free" mempolicy - use nodemask in w.user_nodemask
2205 *
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002206 * Convert a mempolicy into a string.
2207 * Returns the number of characters in buffer (if positive)
2208 * or an error (negative)
2209 */
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002210int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol, int no_context)
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002211{
2212 char *p = buffer;
2213 int l;
2214 nodemask_t nodes;
Lee Schermerhornbea904d2008-04-28 02:13:18 -07002215 unsigned short mode;
David Rientjesf5b087b2008-04-28 02:12:27 -07002216 unsigned short flags = pol ? pol->flags : 0;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002217
Lee Schermerhorn22919902008-04-28 02:13:22 -07002218 /*
2219 * Sanity check: room for longest mode, flag and some nodes
2220 */
2221 VM_BUG_ON(maxlen < strlen("interleave") + strlen("relative") + 16);
2222
Lee Schermerhornbea904d2008-04-28 02:13:18 -07002223 if (!pol || pol == &default_policy)
2224 mode = MPOL_DEFAULT;
2225 else
2226 mode = pol->mode;
2227
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002228 switch (mode) {
2229 case MPOL_DEFAULT:
2230 nodes_clear(nodes);
2231 break;
2232
2233 case MPOL_PREFERRED:
2234 nodes_clear(nodes);
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07002235 if (flags & MPOL_F_LOCAL)
Lee Schermerhorn53f25562008-04-28 02:13:20 -07002236 mode = MPOL_LOCAL; /* pseudo-policy */
2237 else
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07002238 node_set(pol->v.preferred_node, nodes);
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002239 break;
2240
2241 case MPOL_BIND:
Mel Gorman19770b32008-04-28 02:12:18 -07002242 /* Fall through */
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002243 case MPOL_INTERLEAVE:
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002244 if (no_context)
2245 nodes = pol->w.user_nodemask;
2246 else
2247 nodes = pol->v.nodes;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002248 break;
2249
2250 default:
2251 BUG();
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002252 }
2253
2254 l = strlen(policy_types[mode]);
Lee Schermerhorn53f25562008-04-28 02:13:20 -07002255 if (buffer + maxlen < p + l + 1)
2256 return -ENOSPC;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002257
2258 strcpy(p, policy_types[mode]);
2259 p += l;
2260
Lee Schermerhornfc36b8d2008-04-28 02:13:21 -07002261 if (flags & MPOL_MODE_FLAGS) {
David Rientjesf5b087b2008-04-28 02:12:27 -07002262 if (buffer + maxlen < p + 2)
2263 return -ENOSPC;
2264 *p++ = '=';
2265
Lee Schermerhorn22919902008-04-28 02:13:22 -07002266 /*
2267 * Currently, the only defined flags are mutually exclusive
2268 */
David Rientjesf5b087b2008-04-28 02:12:27 -07002269 if (flags & MPOL_F_STATIC_NODES)
Lee Schermerhorn22919902008-04-28 02:13:22 -07002270 p += snprintf(p, buffer + maxlen - p, "static");
2271 else if (flags & MPOL_F_RELATIVE_NODES)
2272 p += snprintf(p, buffer + maxlen - p, "relative");
David Rientjesf5b087b2008-04-28 02:12:27 -07002273 }
2274
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002275 if (!nodes_empty(nodes)) {
2276 if (buffer + maxlen < p + 2)
2277 return -ENOSPC;
Lee Schermerhorn095f1fc2008-04-28 02:13:23 -07002278 *p++ = ':';
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002279 p += nodelist_scnprintf(p, buffer + maxlen - p, nodes);
2280 }
2281 return p - buffer;
2282}
2283
2284struct numa_maps {
2285 unsigned long pages;
2286 unsigned long anon;
Christoph Lameter397874d2006-03-06 15:42:53 -08002287 unsigned long active;
2288 unsigned long writeback;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002289 unsigned long mapcount_max;
Christoph Lameter397874d2006-03-06 15:42:53 -08002290 unsigned long dirty;
2291 unsigned long swapcache;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002292 unsigned long node[MAX_NUMNODES];
2293};
2294
Christoph Lameter397874d2006-03-06 15:42:53 -08002295static void gather_stats(struct page *page, void *private, int pte_dirty)
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002296{
2297 struct numa_maps *md = private;
2298 int count = page_mapcount(page);
2299
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002300 md->pages++;
Christoph Lameter397874d2006-03-06 15:42:53 -08002301 if (pte_dirty || PageDirty(page))
2302 md->dirty++;
2303
2304 if (PageSwapCache(page))
2305 md->swapcache++;
2306
Lee Schermerhorn894bc312008-10-18 20:26:39 -07002307 if (PageActive(page) || PageUnevictable(page))
Christoph Lameter397874d2006-03-06 15:42:53 -08002308 md->active++;
2309
2310 if (PageWriteback(page))
2311 md->writeback++;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002312
2313 if (PageAnon(page))
2314 md->anon++;
2315
Christoph Lameter397874d2006-03-06 15:42:53 -08002316 if (count > md->mapcount_max)
2317 md->mapcount_max = count;
2318
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002319 md->node[page_to_nid(page)]++;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002320}
2321
Andrew Morton7f709ed2006-03-07 21:55:22 -08002322#ifdef CONFIG_HUGETLB_PAGE
Christoph Lameter397874d2006-03-06 15:42:53 -08002323static void check_huge_range(struct vm_area_struct *vma,
2324 unsigned long start, unsigned long end,
2325 struct numa_maps *md)
2326{
2327 unsigned long addr;
2328 struct page *page;
Andi Kleena5516432008-07-23 21:27:41 -07002329 struct hstate *h = hstate_vma(vma);
2330 unsigned long sz = huge_page_size(h);
Christoph Lameter397874d2006-03-06 15:42:53 -08002331
Andi Kleena5516432008-07-23 21:27:41 -07002332 for (addr = start; addr < end; addr += sz) {
2333 pte_t *ptep = huge_pte_offset(vma->vm_mm,
2334 addr & huge_page_mask(h));
Christoph Lameter397874d2006-03-06 15:42:53 -08002335 pte_t pte;
2336
2337 if (!ptep)
2338 continue;
2339
2340 pte = *ptep;
2341 if (pte_none(pte))
2342 continue;
2343
2344 page = pte_page(pte);
2345 if (!page)
2346 continue;
2347
2348 gather_stats(page, md, pte_dirty(*ptep));
2349 }
2350}
Andrew Morton7f709ed2006-03-07 21:55:22 -08002351#else
2352static inline void check_huge_range(struct vm_area_struct *vma,
2353 unsigned long start, unsigned long end,
2354 struct numa_maps *md)
2355{
2356}
2357#endif
Christoph Lameter397874d2006-03-06 15:42:53 -08002358
Lee Schermerhorn53f25562008-04-28 02:13:20 -07002359/*
2360 * Display pages allocated per node and memory policy via /proc.
2361 */
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002362int show_numa_map(struct seq_file *m, void *v)
2363{
Eric W. Biederman99f89552006-06-26 00:25:55 -07002364 struct proc_maps_private *priv = m->private;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002365 struct vm_area_struct *vma = v;
2366 struct numa_maps *md;
Christoph Lameter397874d2006-03-06 15:42:53 -08002367 struct file *file = vma->vm_file;
2368 struct mm_struct *mm = vma->vm_mm;
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07002369 struct mempolicy *pol;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002370 int n;
2371 char buffer[50];
2372
Christoph Lameter397874d2006-03-06 15:42:53 -08002373 if (!mm)
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002374 return 0;
2375
2376 md = kzalloc(sizeof(struct numa_maps), GFP_KERNEL);
2377 if (!md)
2378 return 0;
2379
Lee Schermerhorn480eccf2007-09-18 22:46:47 -07002380 pol = get_vma_policy(priv->task, vma, vma->vm_start);
Lee Schermerhorn71fe8042008-04-28 02:13:26 -07002381 mpol_to_str(buffer, sizeof(buffer), pol, 0);
Lee Schermerhorn52cd3b02008-04-28 02:13:16 -07002382 mpol_cond_put(pol);
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002383
Christoph Lameter397874d2006-03-06 15:42:53 -08002384 seq_printf(m, "%08lx %s", vma->vm_start, buffer);
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002385
Christoph Lameter397874d2006-03-06 15:42:53 -08002386 if (file) {
2387 seq_printf(m, " file=");
Jan Blunckc32c2f62008-02-14 19:38:43 -08002388 seq_path(m, &file->f_path, "\n\t= ");
Christoph Lameter397874d2006-03-06 15:42:53 -08002389 } else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
2390 seq_printf(m, " heap");
2391 } else if (vma->vm_start <= mm->start_stack &&
2392 vma->vm_end >= mm->start_stack) {
2393 seq_printf(m, " stack");
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002394 }
Christoph Lameter397874d2006-03-06 15:42:53 -08002395
2396 if (is_vm_hugetlb_page(vma)) {
2397 check_huge_range(vma, vma->vm_start, vma->vm_end, md);
2398 seq_printf(m, " huge");
2399 } else {
2400 check_pgd_range(vma, vma->vm_start, vma->vm_end,
Christoph Lameter56bbd652007-10-16 01:25:35 -07002401 &node_states[N_HIGH_MEMORY], MPOL_MF_STATS, md);
Christoph Lameter397874d2006-03-06 15:42:53 -08002402 }
2403
2404 if (!md->pages)
2405 goto out;
2406
2407 if (md->anon)
2408 seq_printf(m," anon=%lu",md->anon);
2409
2410 if (md->dirty)
2411 seq_printf(m," dirty=%lu",md->dirty);
2412
2413 if (md->pages != md->anon && md->pages != md->dirty)
2414 seq_printf(m, " mapped=%lu", md->pages);
2415
2416 if (md->mapcount_max > 1)
2417 seq_printf(m, " mapmax=%lu", md->mapcount_max);
2418
2419 if (md->swapcache)
2420 seq_printf(m," swapcache=%lu", md->swapcache);
2421
2422 if (md->active < md->pages && !is_vm_hugetlb_page(vma))
2423 seq_printf(m," active=%lu", md->active);
2424
2425 if (md->writeback)
2426 seq_printf(m," writeback=%lu", md->writeback);
2427
Christoph Lameter56bbd652007-10-16 01:25:35 -07002428 for_each_node_state(n, N_HIGH_MEMORY)
Christoph Lameter397874d2006-03-06 15:42:53 -08002429 if (md->node[n])
2430 seq_printf(m, " N%d=%lu", n, md->node[n]);
2431out:
2432 seq_putc(m, '\n');
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002433 kfree(md);
2434
2435 if (m->count < m->size)
Eric W. Biederman99f89552006-06-26 00:25:55 -07002436 m->version = (vma != priv->tail_vma) ? vma->vm_start : 0;
Christoph Lameter1a75a6c2006-01-08 01:01:02 -08002437 return 0;
2438}